Welcome guest2401! I figured i'd weigh in on the US vs. abroad question. I'm half American and half British, and have applied to PhD's mostly in the U.S but a few in the UK as well. Depending on my results, I might also apply to Sciences Po Paris and University of Copenhagen later on as well.
I'm fairly conflicted. I have lived in Europe (Brussels, then Paris) for the last 2 years both for work and for an MA degree, and I absolutely love it. Also on an intellectual level, its a great fit for me, both in terms of my current MA advisor (who is right in my subfield), and in its methodological openness. In particular, there seems to be much less emphasis here on econometrics and heavy-duty quant methods, which is perfect for people like me who are interested in constructivism (usually more qualitative).
On the other hand, I have at this point consulted with continental European, British, and American professors, and have been told by all of them that it is extremely difficult to get a job in the U.S with a foreign PhD. I hope that they were exaggerating, but they said that it is possible, although not easy to go from Oxford, Cambridge, or LSE into a U.S academic job, but that anything else would be nigh-on impossible. So my feeling is that a U.S PhD will give you more flexibility, allowing you good opportunities to take a job abroad afterwards if you want.