The Space Reviewin association with SpaceNews

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Although it’s called the International Space Station, in reality the US has been the dominant partner in the project up to now, dictating much of its development and also paying the bulk of its costs. (credit: NASA)

The future of American human space exploration and the “Critical Path”

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With the pending end of the space shuttle era in American space policy, critical questions revolve around the issue of how and when the United States will return to independent crewed space flight. The decision is complicated by the fact that the US has long had the prestige of being one of the first two space pioneers, first with the Soviet Union and now with the Russian Federation. Both programs grew out of the Cold War driven global competition that only truly ended in 1991 with the collapse of the Soviet Union. That competition had a warping effect upon both participants in that each self-defined themselves as the dominant player within their political-military bloc, an identification reinforced by possession of the largest and most powerful military forces and economies. With the Cold War’s end and the growth of other states to positions of selective parity with the two former superpowers, space activities become more complicated, with diverse international partners possible and conflicting agendas common. How the US responds to these changes will have great impact on the future of American human space exploration, changes are being forced regardless of US preferences in how affairs are conducted in the future.

Earlier assumptions underlying US space activities

When the space age dawned in 1957, the Soviets and Americans were engaged in a competition in which they initially ran alone, as all other states lagged far behind. Fairly quickly, both states engaged in cooperative space activities with the US engaged more widely, beginning with the Canadians and the Europeans and followed by the Japanese. For the United States, the pattern was clear: the US would engage with space partners as long as the other international participants acknowledged American preeminence and leadership. This posture was buttressed at first by the fact that among the Western allies, the United States was the sole possessor of space launch technologies capable of lifting significant payloads to orbit. This American monopoly was carefully guarded through a series of stratagems, including providing space launch services either free or at such a low cost that competitors were discouraged, or by withholding critical launch technologies by forbidding technology transfers on grounds of security concerns. For societies with smaller economies and national budgets, American willingness to provide such launches was accepted because in the short term there was no alternative. In the case of Canada, willingness to accept American leadership got their Alouette I satellite sent to orbit in 1962 (making them the third country to have a satellite in orbit).

For the United States, the pattern was clear: the US would engage with space partners as long as the other international participants acknowledged American preeminence and leadership.

The Europeans were the first to publicly struggle against this American monopolist behavior by initiating an independent launch program, the Europa, which failed. The project failed due to mismatched components since the program attempted to couple existing launch vehicles into a staged vehicle. However, given ever greater US willingness to restrict other states’ ability to compete economically by refusing to launch communication satellites that might pose future challenges to the US monopoly over Intelsat comsat purchases, the Europeans embarked subsequently on a successful launch vehicle program, the Ariane. Efforts to sustain US control over western space launch ultimately failed due to the conscious choices made by various states to compete, combined with the space shuttle Challenger accident in January 1986. That accident led to the subsequent withdrawal by President Reagan of space shuttles from commercial launches. Constricting Japan’s possible competition with US launch vehicles was facilitated by apparent American generosity in licensing certain rocket technologies to the Japanese, combined with no-compete clauses in the contracts. In time, Japan was forced to develop its own independent launch capabilities; a process that took longer than expected but was seen as essential for Japan’s space program to grow.

The International Space Station (ISS) program began in 1984 as an American initiative but international partners were considered an early and important component of the program. Europe and Japan agreed to fund and build the Columbus and the JEM (Japanese Experimental Module, later Kibo) labs to house much of the research to be conducted on orbit. Their participation was carefully hammered out in several agreements, but as the space station project floundered in a series of redesigns and budget changes, the partners often became the last to know. In 1993, the Clinton Administration imposed a new design and expanded the partnership agreement to incorporate Russia, with the international partners forced to go along for the ride. Subsequently, in March 2001, the Bush Administration restructured the space station to a new status that the Americans labeled “Station Complete”. For the international partners, this abrupt change was particularly shocking because it envisioned a station possibly incapable of operating the lab components that they were in the process of building. In fact, shortly after the decision, NASA attended a ceremony in Europe celebrating the development of the Columbus space laboratory that the Americans had in effect rendered useless by shrinking the crew size to three from six. By canceling development of the American crew escape vehicle for budgetary reasons, the United States effectively gutted the project. European and Japanese resistance led to changes that reinstated their participation in a more substantial role.

The ISS continues as a bone of contention when in January 2004, the Americans announced their intention to shut down the shuttle in 2010 (now possibly into early 2011) and deorbit the ISS in 2015 or 2016, or in any case have the US abandon the ISS for the Constellation program. That plan is unacceptable to the international partners who want the ISS to operate until at least 2020. Pushing the ISS beyond that date is not impossible, as the Russian space station Mir demonstrated, although it might become dicey toward the end. Those plans are in abeyance at this writing as the Obama Administration explores its alternatives and the new US road for continued human spaceflight, which will also impact the partners.

The point of the above is not to rehearse the past but to point out a pattern in US government international cooperative activities with other states whether in space launch, human space exploration, or space science and other research projects. The historical pattern is simple: the US is willing to join international space projects as long as it remains the project leader and is relatively, if not completely, unconstrained by the international partners when the US decides significant changes are required. Why would other states agree to such arrangements? First, the United States, due to its resources, often set out to establish a new program and then added other participants on as second thoughts. This happened with the space shuttle: Europe and Canada came on after the original configuration was established. Likewise, the ISS was basically configured as a concept and then the international partners brought on board.1 As a result, historically, the US, as its price for being leader, was normally willing to pay the largest share of the costs, which for space operations are usually significant and long-term due to recurring program delays and cost overruns. By being willing to pay the costs, the United States encouraged a “free rider” mentality among its partners—meaning their willingness to accept US decisions only as long as the US wanted to pay.

Second, and of obviously declining importance today, the United States previously controlled the critical step in the project, the ability to launch the resulting payload to orbit or beyond. The US aggressively pursued a policy aimed at discouraging other states’ efforts to develop significant independent launch capabilities. The Europeans were first to break free, followed more slowly by Japan. Until the 1980s, the United States effectively had a complete monopoly on commercial launches and a large percentage of all launches by the Western states and their allies.

The reality is that the human spaceflight program survives as well as it does because neither political party has truly bought into a pay-as-you-go budget; deficits growing as far as the eye can see have allowed the humans spaceflight program to survive.

Third, in a cynical but realistic tradeoff, other states learned to accept these de facto ground rules in order to have access to the programs and the technologies involved. This allowed states to participate in broader and more advanced space activities than would otherwise have been possible given their budgets. Canada, for example, has a much larger and cost-effective space program than its domestic political realities would normally envision. Canadians as individuals participated in the Apollo program, with a significant colony of Canadian engineers working at the then-Manned Spacecraft Center (now Johnson Space Center) as members of NASA teams working on ensuring successful Moon landings and returns. Their presence was the direct result of the cancellation of the Avro Arrow fighter aircraft by then Prime Minister Diefenbaker, another brain drain to the United States. Canada subsequently participated in the shuttle program with their Remote Manipulator System (RMS) known as Canadarm, used for moving awkward and heavy payloads out of the shuttle. Later, in the ISS program, Canada reprised its Canadarm experience by building the Canadarm2 for the ISS. As a result of this activity, Canada has been able to support a human spaceflight program without the cost of independent launch. More broadly, Canada has been able to link up with the European Space Agency to engage in other activities outside US control.

For the Europeans, there existed an alternative once the European Space Agency (ESA) became established, but that was largely not for human spaceflight. Their willingness to support the costs of such an endeavor was obviously limited but subject to change as opportunities arose. An independent European crewed spaceflight program was considered several times, but the US always provided a cheaper option provided the Europeans were willing to accept American leadership, erratic at times due to a constantly shifting domestic political environment regarding covering the costs of human spaceflight. There is little major disagreement that the US should not be involved in such prestigious activities but the funding question always comes wrapped in a comparative cost analysis: the shuttle versus tax cuts or the shuttle versus environmental programs. The reality is that the human spaceflight program survives as well as it does because neither political party has truly bought into a pay-as-you-go budget; deficits growing as far as the eye can see have allowed the humans spaceflight program to survive. One forgets that Eisenhower was skeptical about the Apollo program due to its costs especially if you wanted to balance the budget—Eisenhower being the last US president to take balanced budgets seriously.

Confronting reality

The pattern has been clear: the US leads and others follow. This unipolar posture, however, assumes that the United States is willing to lead in terms of paying the major portion of the costs of any international space project. The likelihood of the Obama Administration dropping or ending the US human spaceflight program is low given the prestige and other considerations that have undergirded US human space exploration since its inception during the Eisenhower administration. Whether the Obama Administration will push forward aggressively or, more likely, seek alternatives is unimportant except that the United States will continue in whatever configuration is agreed upon.

What has become clear since the 1980s is that the United States is unwilling or unable (take your pick as to the relevant explanation) to singlehandedly pursue a large-scale human spaceflight endeavor. This reality was hammered home by the ISS difficulties when international partners became critical components in completing and, more importantly, justifying to Congress continuation of the space station program. Without those justifications, the House of Representatives in 1993 was willing to cancel the space station program (cancelation came within one vote on the House floor). NASA’s now traditional strategy of buying into human spaceflight projects with low-ball numbers is increasingly more difficult to justify. Cost overruns will not disappear, but congressional willingness to accept them is becoming more problematic, especially over the next decade as the United States digs out from under the current economic difficulties.

What has become clear since the 1980s is that the United States is unwilling or unable (take your pick as to the relevant explanation) to singlehandedly pursue a large-scale human spaceflight endeavor.

There are still many who argue for an American go-it-alone strategy, but the reality is that the horse has already left the barn. The ISS, the centerpiece of a generation of NASA dreams, has created the new reality that international partners must be engaged and their contributions are no longer trivial, so their desires and capabilities become important. The critical path for the completion of the ISS in its final configuration incorporates two international partners, Russia and Canada. For the first time, a participant other than the United States is placed in the position that their actions or failure to act will adversely impact project completion. For example, the Russian delay in completing and orbiting their second module, the Zvezda Service Module, to link up with the first Zarya Control Module led the US to construct an Interim Control Module as a backup in case Zvezda was damaged or lost during launch. Zarya had been paid for by the US, with Zvezda being a Russian contribution to the ISS program that was delayed due to domestic Russian financial issues. The Interim Control Module was a diversion of NASA resources felt necessary if the ISS program was to stay roughly on track.

The Canadians, with their Canadarm remote manipulators, are also on the critical path in that use of their capabilities makes the ISS construction process quicker with less necessity for long-endurance and potentially hazardous spacewalks. NASA identified the Canadian contribution on its ISS website thusly: “The installation of the new truss segments and unfurling of the arrays require unprecedented robotic operations. Those operations will use the shuttle and station’s Canadian-built mechanical arms to delicately maneuver school bus-sized station components into place.”2 What is left unspoken is that Canada’s budget issues earlier threatened required a readjustment of Canada’s contribution to the overall cost of the ISS going forward.

What is becoming clear is if the United States is to continue its human exploration program, international partners are going to be critical for any large-scale, long-duration human exploration effort. The thrill is gone as evidenced by the increasing difficulty encountered in mustering political support for NASA’s human spaceflight program. Commercial launch programs are likely to partially replace government vehicles for reaching orbit, but space exploration means going places where there exists no immediate commercial market. The costs are enormous given the likely economic returns. You can subsidize commercial flights but that removes them from economic rationality if the market approach is to work. It is better to keep the two separate because both lose in the exchange.

China and India wax very enthusiastically about future manned missions to orbit, the Moon, and beyond, but have not confronted the funding realities of such long-duration programs against likely benefits. For new national space participants, the thrill is getting there since it marks such a state as a major global technological player, but the reality is that long-term human space exploration efforts become ever more expensive, fraught with unanticipated problems, and plagued by delays. All of these factors will fuel domestic calls for retrenchment and other short-term solutions to budget issues even among the new participants. Fortunately for the United States, we lack the goad of the Cold War although nationalism and other competitive factors will continue to fuel our national space program. Those factors will keep the United States in the game, albeit without the war-type funding Apollo generated.

International options

The current question becomes how the US should approach the question of international cooperation. With the space shuttle’s demise as a flight option, the United States confronts the reality of being dependent upon the good graces of others. That prospect obviously distresses many since this situation may signal the first voluntary withdrawal of a state from independent human spaceflight after establishing that capacity. Given the dynamics of American politics and nationalism, the US is unlikely to actually completely withdraw despite the fact that previous gaps in flight capability have been acceptable.

The United States at least temporarily moves from the position of dominant partner to that of dependent. This status will be uncomfortable but doable as a stopgap.

The full end of the Apollo program in the form of the Apollo-Soyuz Test Project in 1975 left the United States grounded until the space shuttle flew in 1981. However, any anxiety about that gap was minimized by awareness that the shuttle was coming, albeit slowly. The shuttle’s survival as a program earlier in January 1972 had been more tenuous than most realize. President Richard Nixon agreed to start the shuttle program in large part because of its importance for California in terms of jobs; 1972 being a presidential election year and California a critical state. One can make the argument that if President Nixon had understood in January 1972 that George McGovern was to be the Democratic presidential candidate rather than Edmund Muskie or Hubert Humphrey, Nixon may not have approved the shuttle. Nixon would not have needed the California jobs to insure his re-election.

Likewise, each of the two shuttle accidents created some thoughts of cancelation. The problem was that shuttle replacement programs such as the X-33 fell though, leaving the shuttle in place despite its flight hazards. After the Columbia accident in February 2003, the shuttle was no longer considered safe enough to continue as a flight vehicle indefinitely. Prior to that tragedy, the space shuttle was considered viable until 2020 or 2030, but no longer after the Columbia Accident Investigation Board report in August 2003. As a result, now another flight gap looms with great debate over the viability of Ares 1 and uncertainty about other possible substitutes. The practical result is that the US for the next several years will have to buy seats on Russian Soyuz flights, as will other participants.

The United States at least temporarily moves from the position of dominant partner to that of dependent. This status will be uncomfortable but doable as a stopgap. The more critical issue is the declining willingness of presidents and congresses to fund long-term space programs, especially human exploration, because it is significantly more expensive than unmanned missions. How NASA is able to fund such programs in the absence of strong political support remains a difficult question. The degree of difficulty has grown over the years but has not yet returned to the levels of congressional antagonism as in 1993 when the ISS came within one vote of cancelation on the House floor while its budgetary competitor, the Superconducting Super Collider, was terminated.

There are no easy answers but obviously one approach may be for the United States to fully opt into international partnerships led by a consortium of states with the US as one partner among others. Participation by each state would vary from mission to mission, but would allow continued US support for a manned space program. Such alliances can be critical for sustaining such programs despite the annual congressional and presidential appropriations process that provides repeated opportunities for budget cuts and stretch outs. Politically, international partners become arguments for continued US participation; otherwise, the US loses standing in the international community.

What this means is that the US must become comfortable with such close cooperation, as unilateral decisions with no prior consultation with partners will end. The advantage is that true cooperation translates into greater equality in terms of budget share—the US will no longer operate as the funder of last resort with the unpleasantness that situation generates. One downside is that projects will move more slowly (although in truth no one may notice, given the delays common presently) due to the need for effective consultation among the partners before programs are initiated and necessary changes are made. Such partnerships provide a mechanism for incorporating different states into the program based on actual interest and capabilities.

The reality is that NASA struggles to implement a human spaceflight program that is broken. The program is broken not because of technical failure but because the political base has eroded to the point that a new political arrangement needs to be developed.

In fact, a model for considering such an approach would be ESA, where a diversity of states in terms of resources and technological capabilities work together to develop and implement a long-term space exploration program. ESA does not eliminate the differences between partners—the larger states dominate based on their willingness to contribute technologically and budgetary. States also have the option to not participate in certain programs that do not meet their national priorities. The British, for example, opted out earlier from certain programs, most notably Ariane, but now wishes to reengage more proactively in ESA programs.

The reality is that NASA struggles to implement a human spaceflight program that is broken. The program is broken not because of technical failure—although there has been some of that—but because the political base has eroded to the point that a new political arrangement needs to be developed. The United States is two generations beyond the impetus that generated Apollo; that is truly history now. The task now is building a future. Apollo was the product of the Cold War. The new era is more fluid, but that does not mean a new justification and approach cannot be created.


  1. James Zimmerman, “International Configurations,” Projects: Aim for Mars, Stepping into the Future: A Workshop in Memory of the Columbia Seven, April 29-30, 2003, The Planetary Society (accessed December 21, 2009); and John M. Logsdon, Together in Orbit: The Origins of International Participation in the Space Station (Washington, D.C.: NASA History Division, Monographs in Aerospace History #11, November 1998).
  2. NASA, “Space Station Under Construction: Building a Ship Outside a Shipyard,” (accessed December 24, 2009).