The isolationist point of view is that the Islamic terrorists attacked us for interfering in their realm (how exactly I wonder? - we saved their Kosovo friends, and saved Egypts face in the Yom Kipper, but anyways....). They say if the US pulls all its troops homes and hunkers down in the homefront the Islamists will forgive us and focus on Israel and Europe and maybe India.
Sorry, but the naivete of that belief is beyond belief. Do they realize they are on the same page with Chris Mathews and Noam Chomsky when they say things like that?
I will even concede that in WWII, had the US stayed isolationist that, it is very likely that Japan and Germany would have just let the US be - since an invasion and occupation of the United States is impossible. But these are new times and we face a new enemy with objectives entirely different than territorial occupation.
If that were true, Paul can not necessarily chose who supports him. Could you name one isolationist or anti-Semite who supports Paul? I do not know of any.