The image says it all. The official photo for the 2013 APEC summit has Secretary of State John Kerry (standing in for the president) tucked away on the side in a back row, while Presidents Xi Jinping of China and Vladimir Putin of Russia take center stage. While Putin and other Asia-Pacific leaders strongly defended Barack Obama's decision to stay at home to deal with the crisis engendered by the shutdown (with the Russian leader declaring, "If I was in a similar situation, I would not come either. Nor would any other head of state"), the United States will stay pay a political price to its position in the Asia-Pacific region by not having its chief executive present.

But it also raises the question: why was Vice President Joe Biden not sent in Obama's stead?

This is to offer no offense to Kerry, who has demonstrated a real affinity for diplomacy. Moreover, in developing a good working relationship with a number of his counterparts, especially Russian Foreign Minister Sergei Lavrov, Kerry has been able to make progress on a number of stalled issues. But Kerry has two vulnerabilities that have weakened his possible effectiveness.

The first is that he has not been able to establish himself as a credible "alter ego" to the president in foreign affairs. He is not seen as definitively speaking with Obama's voice. Kerry's claim was undermined by the events that led to the volte-face on U.S. policy towards Syria. Having laid the groundwork for a U.S. strike in response to the use of chemical weapons in the Syrian civil war, particularly in an emotional address only hours earlier, Kerry was apparently caught by surprise after Obama's famous "stroll around the grounds" with Chief of Staff Denis McDonough on the evening of August 30 that led to the president deciding to hold off on military action and to seek Congressional authorization. Kerry certainly has claim to be one of the voices advising the president, but cannot claim to be any sort of "vicar" for U.S. foreign policy in the second term Obama administration.

This means that all of his statements and promises—ranging from the continued U.S. commitment to the security of the region to an American pledge to move forward on the Trans-Pacific Partnership—are taken with a grain of salt, and especially whether Kerry's passionate defense of America's interests in the region will likewise fall victim to U.S. domestic politics.

The second is a matter of protocol. Biden would have a better claim than Kerry to be treated as an appropriate stand-in for the president. It is easier for other governments to accept the vice president as a replacement for the president than the secretary of state. Al Gore's tenure as vice president established the precedent that the American VP was the appropriate interlocutor for prime ministers in other governments (especially Russian prime ministers Viktor Chernomyrdin and Yevgeny Primakov). More recently, we have the precedent set at the 2012 G-8 summit that a president unable to attend (in this case, Vladimir Putin, who also claimed to have pressing domestic matters to settle) that a prime minister would be treated as a near-peer of the other heads of state. Citing the Medvedev precedent, Biden could have been dispatched to Indonesia (and then to Brunei for the East Asia summit).

Throughout his tenure as vice president, Biden has been dispatched as a troubleshooter for the administration on foreign-policy issues. Earlier this year, he "tracked" the visits of key Chinese officials to Latin America, following up by continuing to stress America's engagement with the countries of the hemisphere. It was Biden who made critical visits to India and to Brazil, in an effort to reassure these rising powers and leading democracies of the global South of continuing U.S. engagement. My guess is that a number of key Asian leaders—who were counting on the opportunity to be able to converse directly with Obama—would feel better served by returning to their countries by being able to point to substantive conversations with the vice president rather than the secretary of state.

Perhaps Biden was kept in Washington out of a sense that his domestic political experience would help to resolve the government shutdown. But the government of the world's sole superpower has to be able to walk and chew gum at the same time; the rest of the world does not set aside its business to accommodate the U.S. political calendar. There may also be concerns, based on earlier signs, that Biden might be setting himself up as the "heir" in order to better facilitate a run for the White House in 2016; a photo-op of him "looking presidential" could enhance those efforts. I hope that these calculations did not enter into the picture, for if Biden's presence at the APEC and East Asia summits could produce more dividends for the United States, in terms of reassuring now increasingly jittery allies that the United States is not serious about its pivot to Asia, then he should have gone.

No doubt the mantra in Washington is that this will all be fixed later. The United States will not disappear as an Asia-Pacific power overnight, but when even close allies like Australia make time to court China (the new prime minister Tony Abbott's first bilateral meeting was to have been with Obama—but instead was held with Xi) Washington cannot take any country in the region for granted. At any rate, the Obama administration, once the shutdown crisis is resolved, will have to be prepared to make a full-court press to regain the initiative in the region if its rhetoric about the pivot to Asia will have any remaining credibility.

Nikolas K. Gvosdev, a senior editor at The National Interest, is a professor of national-security studies at the U.S. Naval War College. The views expressed are entirely his own.