I think that what you are experiencing as far as a "New Era of Terrorism" is, to some extent, the 24 hour news cycle, combined with social media. Terrorism has existed for a very long time on a major scale. Modern travel has made it easier for terrorists to travel. The internet has facilitated spreading the words of terrorists and allowed them to recruit world wide.
I am OK with the level of security we have here in the US. I would not want to live in a police state. I would much rather live a free life and deal with the risks involved, than have my movements restricted on a daily basis in the name of security. I don't know for sure if restrictions would hamper terrorism anyways. It could be that they would still find a way.
There is one way we could quickly make it more difficult though. If you are a terror suspect and are on the no fly list with the TSA, you should not be able to buy guns, ammo, or anything of the sort. The second amendment should not protect those who wish to do harm to innocent civilians.
On the flip side, we should allow open and concealed carry without restriction. An armed civilian is less likely to become a victim IMO. If these terrorists weren't shooting fish in a barrel, their body counts would drop significantly.