My recollection is that politics resumed about two weeks later, with the Democrats demanding to know why George Bush hadn't warned the country that the attack was going to happen, and why he let members of the Saudi royal family leave on a special flight after the aircraft ban was in force.
Just 2 weeks after the attack, Letterman was the first to make fun of President Bush. Then everyone else piled on.
That was the last time I watched any of the late night buffoons.