Ebola and Political Authority

My sense from listening to the news on the Ebola crisis is that many of those from the liberal side in the media (i.e. most of the mainstream media) have the view that the proper end of the U.S. political authorities is to promote global welfare. For instance, it just seems obvious to some that the President should be at least as concerned with the plight of those in Sierra Leone if not more so than with U.S. citizens, such that it's unthinkable that he temporarily block flights of persons from certain countries or of persons exposed to Ebola.  It seems obvious to some that it is wrong to give experimental medications first to U.S. citizens and secondarily to non-U.S. citizens (or perhaps not at all due to their experimental nature, lack of proper consent, etc.)  Some of the background assumptions, here, seem at best utilitarian, at worst Marxist.