Julian Sanchez explains what Barack Obama and George W. Bush really have in common:

What I find striking is the background assumption that whether the United States military has a role to play here is taken to be a simple function of how much we care about other people's suffering. One obvious answer is that caring or not caring simply doesn't come into it: That the function of the U.S. military is to protect the vital interests of the United States, and that it is for this specific purpose that billions of tax dollars are extracted from American citizens, and for which young men and women have volunteered to risk their lives. It is not a general-purpose pool of resources to be drawn on for promoting desirable outcomes around the world.

A parallel argument is quite familiar on the domestic front, however.

Pick any morally unattractive outcome or situation, and you will find someone ready to argue that if the federal government plausibly could do something to remedy it, then anyone who denies the federal government should act must simply be indifferent to the problem.

My sense is that many more people tend to find this sort of argument convincing in domestic affairs precisely because we seem to have effectively abandoned the conception of the federal government as an entity with clear and defined powers and purposes. We debate whether a particular program will be effective or worth the cost, but over the course of the 20th century, the notion that such debates should be limited to enumerated government functions largely fell out of fashion. Most peopleor at least most public intellectuals and policy advocatesnow seem to think of Congress as a kind of all-purpose problem solving committee.

And I can't help but suspect that the two are linked. Duties and obligations may be specific, but morality is universal: Other things equal, the suffering of a person in Lebanon counts just as much as that of a person in Lebanon, Pennsylvania. Once we abandon the idea of a limited government with defined powersjustified by reference to a narrow set of functions specified in advanceand instead see it as imbued with a general mandate to do good, it's much harder for a moral cosmopolitan to resist making the scope of that mandate global, at least in principle.

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