Why no assasinations?

What's with this taboo on assasination that the US government seems to have?  Why is it such a bad idea to send a covert unit to kill the leader of your enemies instead of carpet bombing the whole damn country, causing the deaths of hundreads of troops and civillians and costing billions of dollars? 

Assasination is a fuck good idea!  Why discount it in whole?

>>2
You're stupid.  Stop acting like we have any actual beef with the Iraqis, when all we really want is their oil.

>>5
You're basically advocating propaganda speak.  That is, language designed to send people into an emotional frenzy without really understanding why.  If you want to hate the US government, hate them for the fact that they actually have killed civillians over their own interests.  I can actually understand charges like that.  Don't make up some false charge of genocide, which should only be used in situations like >>3 described.

Asassination hasn't really been addressed so far.  Would someone care to respond who doesn't believe in evil?