"Larkin wrote of the withdrawal of the last British troops from stations in the British Empire.

Whether one thinks this is a good thing or a bad thing depends rather on whether one thinks that having an Empire is a good thing or a bad thing. "

I think having an empire is a pain in the ass. But in the short term there are more important issues. Historical, and I see no reason why it would be any different at the present, the ending of even minor empires has the direct result of increasing the level conflicts in those areas that a empire had influence. The middle East's relatively recent history of conflicts can be traced back to collapse of Ottoman empire and then after this from weak attempt by French and British empires.

Regarding the "American Pax Empire":

" "The Benevolent Empire"

But Boot in fact is willing to use the term "imperialism" to describe United States policy, not only in the early 20th century but "since at least 1803", though this is primarily a simple difference in terminology, since he still argues that US foreign policy has been consistently benevolent.[29] Boot is not alone; as conservative columnist Charles Krauthammer puts it,, "People are now coming out of the closet on the word 'empire.'" This embrace of empire is made by many neoconservatives, including British historian Paul Johnson, and writers Dinesh D'Souza and Mark Steyn. It is also made by some liberal hawks, such as political scientist Zbigniew Brzezinski, and Michael Ignatieff."
http://en.wikipedia.org/wiki/American_Empire

I think a better grasp of American empire rather than Pax or Benevolent, is better understood as seeing as vast Welfare State Empire- friendship and kindness are not really the issue.
Anyhow, the ending of the global American empire with a world possessing nuclear technology has a good chance of being less far less gentle than previous horrors that follow an empire's collapse.
But in their deepest of hearts I don't think lefties care if billions of "less fortunate" people's of world suffer and die- as long as it isn't on the TV set too much of the time and doesn't directly affect their life.