Careful how you cast stones there, FRiend.... It's just as easy and just as valid to say the same thing about conservatives. Who among the leaders (so-called) of the Conservative movement can boast the intellectual credentials of a Buckley, Kirk, or Reagan? (Are those crickets I hear...?) Who, on the other hand, can you name who plays to the emotions of conservatives? (Palin, Limbaugh, Hannity....?)
The problem isn't so much in a person's political outlook, though -- you can see the same thing on both sides. It's the culture.
We live in a culture that promotes and rewards immediate emotional gratification.
There's no patience anymore for extended, rational debate. The media are geared toward short attention spans and 6th grade reading levels, and (apparently) that's what most people want -- it's a feedback loop. (To see just how far we've fallen, I suggest you go look at some of Homer_J_Simpson's posts from the NYT of 70 years ago.)
As for politics ... it's all about getting the sound-bites (and getting paid off by lobbyists). Compromise is grounds for excommunication (the frequent and mindless use of "RINO" being a prime example). Even the "Tea Party" movement is an essentially emotional response to legitimately bad government policies.
And when it comes to something like Sharia law ... the response is again, mostly emotional on both sides of the question.