After all, look who is father is. Clearly he knows better, and has had (through his father) an insider's education and perspective on the mass-murder, fraud, hypocrisy, corruption, and naked dishonesty that is U.S. Foreign Policy (and "funding Defense").
Of course he should be held to some standard of Integrity here, and be expected to vote it down.
The fact that he does not do that is alarming. It means that he is just another Mitt Romney - George Bush - John McCain style Republican, and not willing to speak out or step up for any serious change.
And the correct thing to do if a Neocon calls you an isolationist is to say that you wear their criticism as a badge of honor - and then point out how wrong and tragic their judgement has proven to be.
Want DP delivered to your inbox daily? Subscribe here: