Suppose President Bush just flat out lied about the WMD, that it was all just a cover for invading Iraq. This would be completely different from FDR's cirumlocutions to cover his gettting us involved in the European theater of WWII.
But I do see a parallel with the defense of Clinton (not too strangely since it's to a large extent the same people). In both cases the focus is on the basic act (bonking the intern or trying to build WMD) while completely ignoring the open defiance of law and comity. I just heard part of an interview with Senator Bumpers and he still maintains that the issue was the physical deed with Lewinsky, not the lieing, the perjury or the abuse of power (such as using the Cabinet as a propaganda tool in what was effectively a private legal matter). In the same way the focus on WMD is the same kind of narrow focus with the same purpose — to excuse and disregard the other crimes committed in conjunction with the basic infraction. If one just asks “were WMD found in Iraq” one can evade the question of whether the Ba'ath had any obligation to cooperate with the UN and the US in looking for WMD or to comply with the terms of the ceasefire. The logic is that if no WMD are found then any crime committed with regard to WMD is irrelevant. It's all about political battles in the US.
It's the new isolationism, not ignorance of foreign affairs but their complete subordination to domestic political agendas and perforce a complete lack of concern about what is going on in the world outside of the US. Is that not the essence of isolationism?