Tom Rogan puts a different spin on the “credibility” argument, but it still doesn’t make any sense:

In U.S. foreign policy, false resolve is far worse than honest disinterest. Clear disinterest in one area allows us to maintain our credibility elsewhere, but when we abandon our word, American credibility is gutted everywhere.

I agree that “false resolve” is something to be avoided, but the reasons for this have nothing to do with “credibility.” The problem with pretending to have made a more significant commitment in a place than the U.S. actually has is that it provides false encouragement to the people in that country, it causes them to expect help that isn’t coming, and it may even lead them to take dangerous actions that they would otherwise choose not to take. It creates an illusion of solidarity and support when little or no concrete assistance is forthcoming. In short, it is cruel and misleading. But does it have any effect on whether America’s promises and threats are believed elsewhere? No, it doesn’t.

For one thing, other states don’t assess U.S. willingness to back up commitments in one place based on its willingness to do so elsewhere, but focus instead on U.S. interests and capabilities in that part of the world. How much more are other states going to ignore “false resolve” in this one case when they are quite ready to ignore a lack of resolve in other cases? We can see how unimportant past U.S. actions are to contemporary judgments about future U.S. commitments from the fact that many states and groups still clamor to be made into U.S. clients and proxies despite quite a few examples of how the U.S. has discarded both over the decades. One might think that governments and rebel groups alike would have learned from past U.S. actions that U.S. support for clients and proxies can be unreliable and inconsistent, but that doesn’t seem to discourage any of them from calling for U.S. support whenever possible.