David Isenberg, an arms control and national security expert, has written two in-depth articles about America's "imperial overstretch," which you can read
here and
here.
None of the viable Democratic candidates will touch this question, and among the non-viable, only Kuchinch would do so. But even if he were elected, he could do very little. The same holds true of Dean. Candidates like Kerry and Edwards can be counted on not to challenge American imperialism in any fundamental way. How much longer we will have before this imperialism leads to a potentially irreversible catastrophe of global proportions remains unclear.