Trump and the Republicans (and to a slightly lesser extent, Clinton and the Democrats) would have you believe that terrorism is a new problem, and one of our biggest problems. Neither of those ideas is true.
The truth is that presidents have had to deal with terrorism for a long time. The chart above (made with info from johnstonsarchives.net) shows the deaths from terrorism in the U.S. since 1949. Note that there have been deaths from terrorism in every one of the presidencies since that date. And you can go back much farther than that. For instance, the death of President Lincoln was due to a terrorist act.
The only thing that changes is who is responsible for the terrorist acts, and sometimes even that doesn't change much. For instance, the Ku Klux Klan (one of the most infamous terrorists groups in U.S. history) has been committing terrorist acts for more than a century, and still do.
Trump, and his Republican cohorts, would have you believe that the only terrorism we need to fear is that being done by islamic extremists. Again, not true. The truth is that, while islamic extremists do commit terrorist acts in this country, more deaths are caused by home-grown right-wing terrorists in almost every year. The muslim terrorists are no better or worse than the other terrorists that strike every year in the United States.
And the fear of terrorism generated by our politicians and media is way out of whack to the real dangers facing American citizens. Americans are far more likely to die from a myriad of other cause than terrorism. And if you just want to talk about violent deaths, Americans are far more likely to die from gun violence than from terrorism.
Note the chart below (from cnn.com). Since 2001, an American has been 120 times more likely to die from our home-grown gun violence than from a terrorist act, and most years the number is even higher (in 2013, the number was 1600 times as likely). We do have an epidemic of violence in this country, but it is not from muslim terrorists. It comes from the easy access to any kind of gun by criminals, domestic abuser, and the dangerously mentally ill.
The sad thing is that we could take reasonable (and constitutional) measures to reduce gun violence in this country, but our politicians refuse to do it. Those politicians (especially the Republicans) won't even do something as basic as making sure all gun buyers must have a background check before being allowed to purchase a gun (even though over 80% of all Americans want that).
Our politicians are more than happy to drum up fear against muslims, but they refuse to do anything about the real dangers that face Americans. Those politicians should be ashamed of themselves, but they have shown many times that they are incapable of shame (or any degree of morality).