Terrorism can be a scary thing, I get it. That's the purpose. Sometimes we forget because we disassociate the word in our minds, but terror is fear. So if you react by being afraid, by not wanting to go places, then you are serving their goal.
The likelihood that you would be hurt in a terror attack is so slim, you are probably more likely to win the lottery. I mean, really, this stuff can't keep you from living your life! If you avoid Mall of America on Black Friday or airports during holidays, you're feeding their goals. You are interrupting your normal life because of fears you have, and it's ridiculous!
There are these people out there who hate you, terrorists, and they hate you because of the way you live your life. They hate you for being "Western" or "Christian" or "gay" or "American." They hate you for things you would never change, and so you shouldn't worry about it
I'm headed to Germany soon, and just this past week, there were two attacks in the country I will travel to. I plan to travel throughout Europe, and I won't stop to take precaution for the random attacks that may or may not happen. Wearing your seat belt in a car as a precaution to getting in a car accident makes sense. There is a simple thing that you can do to protect yourself. But terror? Carrying a gun won't help, staying in won't help — there's nothing you can do. And not living your life isn't the answer.