Here are some areas where they differ, even if slightly:
Russia: After Russia invaded Ukraine last year, Rand Paul called for sanctions against the invading nation. Ron Paul warned against that, saying it could sink the U.S. dollar.
The NSA: Ron Paul wants the National Security Agency eliminated. Rand Paul says he's more interested in reining it in.
NSA leaker Edward Snowden: Rand Paul thinks Edward Snowden should receive a light punishment—such as a