Here are some objective, true facts about terrorism, Islam, Trump's travel bans, and refugees (and some other stuff too):
According to the CATO institute - a well-respected, conservative-leaning Think Tank - 17 people from the countries Trump targeted in his executive order have been convicted of committing or attempting terrorist attacks on U.S. soil. This includes six Iranians, six Sudanese, two Somalis, two Iraqis, one Yemini, and zero Libyans or Syrians - which is where most of the refugees come from! Of those 17, precisely zero of them actually ended in anyone being killed. None. Nada. Not a single death. 0.0000000000000% chance, well and truly zero.
Source: cato.org
More CATO institute facts: of the 3.2 million refugees admitted to the United States since 1975, 20 of them have attempted to commit a terrorist attack - meaning 1 in 162,625 refugees admitted to the U.S. were terrorists. And among those, only 3 Americans were killed, total. That puts the risk of being killed by a refugee terrorist at a whopping 1 in 3.6 billion per year. Which is reaaaaaaally close to zero, like rounding-to-eight-decimals-makes-it-zero close. Oh, and all 3 of those were in the late 1970s.
Source: cato.org
(And before you say, "But we don't know what *future* refugees are going to do! And besides, any number of terrorists is too many," I want you to sit down and think for a second about why that is an inherently flawed argument that could be applied to shut down *any* potential risk.)