First of all i must admire your nick 'Valiant'
brave, courageous (y)
Dear Valiant,
IR, US history and I.law will complement each other. Similarly, Muslim law and Islamic studies will complement each other. Read and analyze the syllabus of both papers and then make a decision. Both I.law and M.law are interesting and challenging. As for my opinion, I prefer I.law more and recommend you as well.
Best of luck.