Why has the Obama administration invested so much of its political capital in the resetting of relations with Russia? Why is getting passage of New START seen as so critical to the president's foreign-policy legacy?

Russia has a way of creeping back onto the agenda of American presidents. Bill Clinton was going to focus on the U.S. domestic economy, implicitly critiquing George H. W. Bush for spending so much time managing the relationship with the Soviet Union and then the newly formed successor states—yet America's first "post–Cold War" president had a record number of meetings and summits with Boris Yeltsin. The George W. Bush campaign claimed that under their watch, Russia would not be at the center of its foreign-policy agenda, and lambasted the Clinton team for overemphasizing the "Boris and Bill" connection—until Bush himself had his Putin moment. Obama was supposed to be ushering in transformational change in U.S. foreign policy—notably to fulfill the promise of being America's first Pacific president—and yet, Russia found its way back to the top of the agenda—and like George and Bill before him, Barack has a special relationship with a Russian president, this time Dmitry Medvedev.

This is not to argue that START is not an important agreement, or that Russia is still not one of the major powers helping to shape and set the global agenda. One would expect that the U.S.-Russia relationship will still be something directly handled at the president's level. But what is surprising is the extent to which the president's political team seems to be relying on its diplomatic efforts with Moscow to help legitimize the administration's stewardship of foreign affairs: Russia becomes the yardstick to measure success or failure in bringing about "change."

This may be because so many other ambitious (and not so ambitious) plans have not come to fruition—at least not in the eyes of the political consultants, who are looking for easily packaged and promoted sound bites. There has been no major breakthrough in the Arab-Israeli peace process, despite the efforts of Special Envoy George Mitchell. The attempt to engage Iran produced no tangible benefits, no start of a diplomatic process aimed at reducing tensions (and the most recent round of talks have essentially been a nonstarter). When in opposition during the Bush administration, the Democratic Party's foreign-policy establishment often hinted that Bush's "neoconservatives" had severely disrupted trans-Atlantic relations, whereas Democrats, once back in charge at Foggy Bottom, would quickly rebuild Euro-Atlantic cohesion—but Obama found Europeans no more anxious to lend full-hearted support, particularly to the mission in Afghanistan, than his predecessor—in the sense that while more European troops are now present in the Hindu Kush, the Democrats did not succeed in turning Afghanistan into more of a 50/50 proposition for the alliance. Candidate Obama promised change when it came to U.S. policy in Iraq—but has, as president, largely adhered to the script developed by the previous team. The news from Afghanistan is mixed—but the president did not get the knockout success from the Marja offensive that would decisively shift public opinion—in both Afghanistan and in the United States—to the view that we have reached a critical turning point. The attempt to reach out to China to forge a possible "G-2"—based on much closer cooperation and coordination between Washington and Beijing to solve global problems­—has run up against increased confidence in China that the correlation of forces is increasingly tilting in the PRC's favor. While the administration has begun to rebuild ties with Asian partners that had been somewhat neglected (because of an over-preoccupation with Iraq during the Bush administration), U.S. leadership in the Asia-Pacific region is neither uncontested nor firmly reestablished—and this will be a long-term process at any rate.

Finally, we run up against the political calendar. A president is always under pressure from his political team to focus on short-term deliverables. The long, hard slog of forging truly new partnerships—with India and Brazil, in particular—would not generate dividends for years to come.

So we come back to Russia. For one, the U.S.-Russia relationship had deteriorated to such a point—with many of us wondering whether we were on the verge of a new Cold War back in 2008—that any signs of improvement would redound to the credit of the president's team—and could show one area where Obama's new approach had in fact generated positive results. In contrast to finding breakthroughs on Iran or Israel-Palestine or reorienting relations with the major rising powers of the South and East, resetting relations with Russia could offer some immediate benefits that "could be taken to the bank."

The other reason for the focus on Russia is the sense that improved ties have had spillover effects in other realms—we got a new UN sanctions resolution on Iran; Russia will not deliver the S-300 system to Tehran; the "northern route" to Afghanistan is secured, at a time when the "southern route" via Pakistan has suffered closures; and the reset has helped America's own relations with Europe, both old and new. It has been comparatively easy to measure the metrics of the reset—and the pièce de résistance is a good old-fashioned arms-control treaty.

But is there a next page? Once the current reset agenda has been fulfilled, do relations move to the next level? This is where we may run into difficulties. As Russia's decision to acquiesce to the Chinese démarche and boycott the Nobel Peace Prize ceremony demonstrates, U.S. and Russian perspectives on world affairs still do not align. Both sides have compromised, up to this point, to get things of importance (the Russians imposing more stringent sanctions on Iran, the U.S. delinking the Georgia question from the 123 agreement and so on). But even Medvedev may be reaching the limits of what he can offer Washington and the extent to which he can accommodate U.S. preferences before this impinges on key interests of powerful stakeholders in Russia—and an Obama administration that no longer commands a congressional supermajority and is beginning to gear up for a fight for its very political survival may not be able to offer the additional set of incentives to gain Russian support to meet a new list of "reset metrics."

So perhaps the administration will, after this year, move U.S.-Russia relations into a holding pattern: working to prevent any deterioration, but unable to move things forward. If so, it raises the question: which world leader will emerge to take Medvedev's place as Obama's partner in change? No one candidate immediately comes to mind.