not caring about the rest of the world might have been OK in the 19th and early half of the 20th century.
It doesn't work like that anymore. The old barriers are slowly but surely being eroded.
The economy is becoming global.
People from all over the world can communicate over the Internet.
although the US is the world's greatest power at this time, it cannot survive alone.
9/11 was a great tragedy, but it shouldn't push this country into isolationism and shouldn't justify use of force abroad in places which pose no threat for the US, purely for economic interests.