Concede that islamic radicalism is dangerous, and that an honest debate can be held on whether or not we should be in the middle east.
Then ask them why we need to be occupying Germany or Japan. Once they concede that having massive military presence in those 2 countries simply amounts to a massive economic stimulus for them (both in terms of our tax dollars being spent there and in terms of them not having to pay for their own defense), then you add South Korea to the list. The might balk, as North Korea is "dangerous". Then you point out that North Koreans are eating tree bark because they're starving, and that if North Korea invades South Korea, they're going straight for the McDonalds.
Ultimately the point that I've gotten to with several people is that, while they may not specifically agree with him on middle east policy, Ron Paul has a lot of good points with regard to foreign policy in general, military over-extension and overspending, and his fundamental desire to bring our troops home. When they realize that, in truth, they actually agree with MOST of his foreign policy stances, they tend to become a lot more comfortable with actively supporting him as a candidate.
Nobody agrees with any candidate on everything. So if you can convince them that their disagreement with Paul is with regard to a specific application (middle east) of a broader philosophy that they actually DO agree with (getting rid of global militarism and empire building), then they come around rather quickly.