In my reading I often run into complaints about the U. S.’s abandonment of its role in global leadership. I don’t think that’s something to which we should aspire but I disagree even more with its premise. I don’t think there’s been a decline in the U. S.’s global leadership so much as a complete collapse in international followership.
Since the disintegration of the Soviet Union the major European powers, i.e. the United Kingdom, France, and Germany just decided they didn’t need us anymore. The only times in which putative U. S. leadership has been been involved has been in those cases in which France and Germany in particular wanted to accomplish something, e.g. remove the Libyan government, and they just didn’t care to devote the resources that they would have required to do so.