The question of US credibility always arises when there is a major security crisis anywhere in the world (well, anywhere except Africa, it seems). Will America keep promises to its friends and allies? Will America stand up to Russian bullying or give in to its intimidation of Ukraine, thus encouraging others who want to impose themselves on their neighbours?

As usual, analysts are divided. Tyler Cowen, for instance, accepts that a certain level of US credibility remains intact no matter how many promises it breaks or allies it lets down: 'we can promise Ruritania the moon, and fail to deliver it, and still the world thinks we would defend Canada if we had to, simply because such a course of action makes sense for us.'

But does that logic apply to Asia, he wonders?:

 Still, when it comes to Taiwan, or those Japanese islands, or other Pacific islands, I think...the world does not know our true type.  How much are we willing to risk conflict to limit Chinese influence in the Pacific? Whatever you think should be the case, what is the case is not clear, perhaps not clear even to our policymakers themselves. (In contrast there are plenty of data on the parameters of American preferences toward Middle East and Israel-linked outcomes, and our willingness to incur costs to alter those outcomes.)

That is another way of thinking about why the Ukraine crisis is scary for the Pacific. It is one reason why the Nikkei was down 2.5% shortly after market opening Monday morning (Asia time) and ended up 1.3% down for the day.  The Chinese stock market did just fine.

Anatol Lieven, on the other hand, argues that US intervention in the Ukraine would just distract America and thus strengthen China. Lieven doesn't say it in so many words, but that would in turn weaken American credibility:

We’re now witnessing the consequences of how grossly both Russia and the West have overplayed their hands in Ukraine. It is urgently necessary that both should find ways of withdrawing from some of the positions that they have taken. Otherwise, the result could very easily be civil war, Russian invasion, the partition of Ukraine, and a conflict that will haunt Europe for generations to come.

The only country that could possibly benefit from such an outcome is China. As with the invasion of Iraq and the horrible mismanagement of the campaign in Afghanistan, the U.S. would be distracted for another decade from the question of how to deal with its only competitive peer in the world today. Yet given the potentially appalling consequences for the world economy of a war in Ukraine, it is probable that even Beijing would not welcome such an outcome.

Still, when it comes to Taiwan, or those Japanese islands, or other Pacific islands, I think the first view plays a role.  That is, I think the world does not know our true type.  How much are we willing to risk conflict to limit Chinese influence in the Pacific?  Whatever you think should be the case, what is the case is not clear, perhaps not clear even to our policymakers themselves.  (In contrast there are plenty of data on the parameters of American preferences toward Middle East and Israel-linked outcomes, and our willingness to incur costs to alter those outcomes.)

That is another way of thinking about why the Ukraine crisis is scary for the Pacific.  It is one reason why the Nikkei was down 2.5% shortly after market opening Monday morning (Asia time) and ended up 1.3% down for the day.  The Chinese stock market did just fine.

- See more at: http://marginalrevolution.com/#sthash.Q1krD0gO.dpuf
we can promise Ruritania the moon, and fail to deliver it, and still the world thinks we would defend Canada if we had to, simply because such a course of action makes sense for us.  In this setting, our violation of a single promise changes estimates of our true scope of concern, but it does not much change anyone’s estimate of the true type of the American government. - See more at: http://marginalrevolution.com/#sthash.Q1krD0gO.dpuf
we can promise Ruritania the moon, and fail to deliver it, and still the world thinks we would defend Canada if we had to, simply because such a course of action makes sense for us.  In this setting, our violation of a single promise changes estimates of our true scope of concern, but it does not much change anyone’s estimate of the true type of the American government. - See more at: http://marginalrevolution.com/#sthash.Q1krD0gO.dpuf