First of all, I agree with Dallas Mayor’s assessment that Trump’s travel ban could help radicalize extremists. Whether or not there is any good reason for Trump to order such a ban is not as important as it is how the ban will be seen by the world. I am sorry to have dismissed political correctness. Political correctness is not unimportant in this case.
As to Trump’s motivation for this ban, I can only speculate. There could be a few reasons for Trump to have come up with this ban. There could be an innocent reason for the US to stop accepting refugees from Syria. I was once a refugee. So I know something about how things work for refugees. When conflicts end in the country where they come from, refugees are supposed to go back to their country if they have not resettled in another country. Whether refugees from Syria should still be sent to other countries to resettle there depends on whether conflicts have ended in Syria. Trump probably does not want to think that there are still conflicts in Syria. In reality, conflicts do not usually end so quickly. If Russia is still supporting the Assad regime, conflicts will still be there. Even after all foreign forces have left Syria, there could still be a civil war there. There will be peace there eventually. But probably not right now.
That being said, a lot of people, including myself, feel that Trump’s ban is motivated more by some people’s fear of, or worse, hatred for, Muslims. This is because Trump got into power partly by making promises to people who fear or hate Muslims that he will protect them. When government policies are made out of fear or hatred, they can not be reasonable. Why do some people have to be inconvenienced and disrespected? Human rights are not just for the majority. They are for everyone. If Trump does not want to be misunderstood, he should offer as much explanation for his decision as possible. By simply saying because the US has the need of finding extremists, some people have to be inconvenienced and disrespected, Trump is showing disrespect for these people. I can therefore tell that disrespect is the most important reason for Trump to come up with the ban. Of course, trying to keep his campaign promises, and by extension, keep his job, is another reason.
By the way, if stopping extremists from entering the United States is the reason for the ban, I can not understand why Iran is on the list of countries whose citizens are to be banned. I can only think of Iran being the enemy of Israel as the reason for her to be included.