Answer :

Foreign terrorism only affects us tangentially. Domestic terrorism gives rise to changes in security measures, some of which are very expensive and have caused the economy to falter. 
I was just thinking of the domestic terrorism of the 1970s, carried out by US citizens. This resulted in occasional bomb threats and burned buildings or cars, and occasional shootouts with the police, in which the main casualties were police and the terrorists themselves. Some of the terrorists of that era are now highly respected, well-to-do, and, unrepentant as they are, advisers to the President. If Dzhokhar had escaped, maybe he could have done the same. 
Well anyway, back in those days, the terrorism was in the news but did not affect our daily lives too much, most of the time. I recall being in class at a college, when a "bomb threat" was announced, and the police arrived to investigate. In fact, bomb threats came daily for a week or two. Students and teachers were given the option to evacuate if they chose, but most stayed in class. They did not believe there was a bomb. And there wasn't.the first dragon