Its not a non-sequitur. You were saying that isolationism doesn't work, my argument is that non-isolationism is at the root of US problems with MANY countries.

Sure the US needs to prevent that sort of attack, but one way to prevent it is to avoid the situation in the first place. I don't need to worry about Iran or North Korea nuking me because I live in a country that hasn't had a war of choice with either of them. The price of installing the Shah is still being paid in the need to defend from Iranian retaliation.