For starters, Kerry might be able to convince the UN to become more involved in the rebuilding of Iraq and the establishment of its new government. This won't happen with Bush, since he's already told the UN he doesn't care what they think.
The war on terrorism needs to be worldwide; not a unilateral US effort, imo. In this effort, having allies... and not being universally detested... might be advantageous.
Who is this "UN" and how large is their army? Where do they get all of that money used in rebuilding? How many new governments have they established successfully? Your blind faith in this "idea" is quite telling, Bluflame.
"Unilaterally" fighting the war on terror? Read on:
Since September 11th, a coalition of 90 countries has come together in a fight against terrorism, and that emerging, building, strengthening coalition is changing the way the world does business.
Our partners in the war on terrorism extend far beyond Europe. We're working hand-in-hand with law enforcement officials from Pakistan to Colombia and from Canada to China.
From Feb, 2003 Ashcroft speech to the CFR.
Blueflame, I know you'll dismiss the above quote because John Ashcroft said it to the Council on Foreign Relations, but your BS about the US' "unilateral" war on terror can't stand the laugh test.