Really.  In 2016, a high estimate of all deaths attributable to terror worldwide is 1,286:

https://en.wikipedia.org/wiki/List_of_terrorist_incidents_in_2016

Gun deaths in the US alone average 33,000 per year.  

The low estimate for the Iraq war is 175,000 civilians over 14 years, or at least 12,500 per year.  (Some estimates are as high as 1M).

Terrorism is a scourge, no doubt -- but I think Donald needs to bone up on the numbers before he makes a statement like that.