Why do so many people want to pullout of the wars?

It shows we are weak to the rest of the world. We fight wars to win not to lose them. We should fight to protect our most important ally and also to protect Americans. Terrorists in Iraq and Afghanistan and Libya want to hurt us and our most important ally it is our job to take them out before they take us or our allies out. Pulling out of the war would be foolish and possibly an economic disaster.