WTC was attacked twice, but this first one isn't so "famous". Terrorists detonated a bomb in a truck when it was at parking under one of the towers. But I think terrorists won't strike in August or later, because there will be more police, armed forces and so on.
But Rome! I'm going there in October or November :/
hmmm I'm happy, that I live in such a hopeless, meaningless and poor country like Poland. And at the province, far away of big cities....