Study Russian or Arabic language?

A former student of mine - not a law student, but a high school student about to start university in the fall - emailed and asked whether I would recommend that she study Russian or Arabic as her language. Her interests are a striking combination of science-technology (specifically chemistry and nuclear chemistry) and political science (specifically security studies). Either language would be useful, of course, but I suggested that even though many students have drawn the conclusion that Arabic is the hot language (and, unlike Chinese, actually aquirable as a skill in college), and so it might appear that everyone is already studying it, it is still a highly useful language for someone interested in the technical aspects of proliferation, nuclear terrorism, etc. Russian is obviously useful, but the number of Russian speakers is declining rather rapidly in relation to Arabic speakers, and anyway there are plenty of Russian speakers around in the US. So I suggested she think about Arabic, unless she was passionate about Russian or just wanted to do it - languages require a certain passion, and if you've got the passion, go with it.

Was this good advice to go after Arabic? I also suggested she spend time at the American University of Cairo language program.