[During the August 2006 Lebanon war, t]he Bush administration backed Israel to the hilt and delayed a ceasefire resolution -- just as they are doing now -- in a futile attempt to give Israel time to eke out a military victory. Not to be outdone, Congress passed a resolution of support by a vote of 410-8, after deleting a clause from the initial draft that called for both sides to minimize harm to civilians. The result of all this "support" was a major setback for Israel, however, as the ill-conceived war undermined Lebanon’s fragile democracy and left Hezbollah stronger and more popular than before. Delaying the ceasefire also cost more Israeli and Lebanese lives.
Walt has a point: blind support for Israeli military action often doesn't advance US or Israeli interests, and the Lebanon war was the perfect example. Unfortunately, if we're going to redfine what "pro-Israel" means, I'm not sure the guy who co-wrote The Israel Lobby is the guy who has the bipartisan cred to do it.