I took a look at the acceleration of terror activities by year, and this 'isn't just going away'. Five years to 2004, the US averaged 2.5 terror acts a year. Five years to 2009, the US averaged 4.8 terror acts a year. Five years to 2014, the US averaged 5.5 terror acts a year. And in 2015 until now, the US is averaging 15 terror acts per year.
http://dailysignal.com/2015/09/10/a-timeline-of-73-islamist-terror-plots-since-911/
Although I would edit the following to include domestic terror...the following from the Heritage Foundation is pretty much accurate:
As depicted by this timeline, the threat of terrorism is not receding. Congress should maintain a proactive approach to combatting terrorism, ensuring that law enforcement and intelligence organizations have access to legitimate investigative and surveillance tools. The need for effective counterterrorism operations, though, does not relieve the government of its obligation to follow the law and respect individual privacy and liberty. In the American system, the government must do both equally well. The U.S. should also support stronger action against Islamist terrorist groups abroad to combat those forces radicalizing individuals to attack the U.S.
Don't really get the 'let's do nothing' crowd. But I'm a serious progressive and as you do in any change, build in safe guards rather than find excuses.