I also got into SAIS and SIPA (top 2 choices) and some other schools for IR masters programs. To me, it's always been a no-brainer to get a Masters degree or something higher, like a PhD.
What is it that you do now? If it's not in IR, which you say is your passion, then you may not even be happy in that job 5 years down the line. My opinion is that if I were you in your shoes, with a huge collection of excellent schools to choose from, I would go to school. You may be making over 60k in five years, but in five years with a degree from one of those schools, you could be making much more. If you're really worried about the debt, take a look at the Public Service Loan Forgiveness program.
And having experience trying to get a job in IR with just a bachelor's degree, I've found it extremely hard to even get an internship because Master's students are also applying to these internships while in school. Also, places like DC think tanks and government departments do look more favorably at candidates with higher education. That has just been my experience and just my two cents on your situation!
I wish you luck with this decision and congrats on all those acceptances!
Just wondering if anyone else is applying to the Pickering Graduate Foreign Affairs Fellowship thru the Woodrow Wilson Fellowship Foundation? I just submitted my app, and it sounds like a great deal for anyone who's thinking of a career in the foreign service (or at least doesn't mind serving 4.5 years in the FS upon graduation). Any ideas as to whom this scholarship is geared toward? Past recipients? It's kind of strange that they consider applicants who haven't even been admitted to grad school yet. How sucky would it be to receive the fellowship and then not get into any of my schools? Not likely, I suppose.