Keep them out
According to the punch line of an old joke, Jews react to every news event with a question: Iz dos gut far yidn? (is this good for Jews?).
As we look at what is going on in Europe, we see a fast growing trend of anti-Semitic attacks on Jews. Many young Jews are leaving Europe for Israel, Canada, the United States, Australia, and many
other countries while not seeing a safe future in Europe. Jewish organizations, offices, synagogues, schools, and regular people who look Jewish are permanent objects for attacks by Muslims. Jews feel threatened everywhere in Europe. And now, as hundreds of thousands and maybe millions of Muslims are flooding into Europe, can we say that this is good for Jews?
In the United States the situation is a little better; however, anti-Semitic actions are growing here as well. With the decision by the White House administration to take in 10,000 Syrian refugees, who are mostly Sunni Muslims, we definitely will see a worsening security situation not only for Jews, but also for the general population in the United States.