David E. Bernstein: "Has There Been A Surge Of Anti-Semitism Under And Because Of Trump?"

In short: no.
   This is a really good piece--both the defense and criticism of Trump are sensible:
   First, the defense:

   In the aftermath of the horrific murders at a synagogue in Pittsburgh on Saturday, a good part of the media, social and otherwise, wishes to blame Donald Trump. Surely, Trump's inflammatory rhetoric doesn't exactly calm societal waters, and his remarks on Charlottesville, though often exaggerated by hostile sources, did not exactly come across as a rousing denunciation of white supremacy. Nevertheless, there are some barriers to blaming Trump for anti-Semitic acts specifically.
   First, Pittsburgh was hardly the first time an anti-Semitic gunman murdered people in a Jewish insitution in the U.S. Between the Clinton and Bush II years, there was a shooting at a Jewish Community Center in L.A., a shooting at an El Al counter at LAX, a shooting at the Jewish Federation in Seattle, a shooting at a Jewish Community Center in Kansas City, and a shooting at the Holocaust Museum. Lower levels of vandalism and violence have been even more common. It's true that the death toll in Pittsburgh was especially high, but that's just happenstance; any of the other shoooters would have been happy to kill as many or more. [UPDATE: It's worth noting that many commentators, such as Franklin Foer in The Atlantic, simply ignore these past crimes, and act as if the Pittsburgh murders were some unique event in recent American Jewish history.]
   Second, the Trump administration includes some very strong opponents of anti-Semitism. UN Ambassador Nikki Haley has fought anti-Semitism in the world body, one of the world's primary purveyors of it, with a vigor and effectiveness not seen since at least Daniel Patrick Moynihan. Trump appointee Ken Marcus, head of the Department of Education's Office of Civil Rights, has devoted much of his career to fighting anti-Semitism (but was confirmed over the objections of Senate Democrats, some of whom thought he was too opposed to anti-Semitism too willing to identify certain types of Israel-bashing as a form of anti-Semitism).
   (Some would add here that the Trump administration has been the most pro-Israel in history. While true, I'm not sure that this affects domestic American anti-Semitism one way or another, except perhaps to especially irritate anti-Semites.)
   Those who wish to blame Trump have an ace in the hole, an Anti-Defamation League study that purports to show an almost 60 percent increase in anti-Semitic incidents between 2016 and 2017, which is implicitly blamed on Trump. This study has been cited on over and over in response to Pittsburgh. ... [But the study's misleading]

   Then, the criticism:

Some of my friends tell me that adding reasonable context to the Pittsburgh shooting "excuses" Trump, and thus makes future incidents more likely. On the contrary, I think that reasoned criticism of Trump is useful—for example, noting that Trump's conspiratorial mindset inadvertently feeds anti-Semitism because the latter is a product of the same mindset, or that Trump should have unequivocally rejected support from white nationalists during his campaign, or that Trump is too narcissistic to apologize when he retweeted from anti-Semitic websites, and so on, though I would draw the line at blaming Trump for the incident, unless one wants to also explain why there were similar shootings before Trump, and also talk about all the other currents of anti-Semitism on both left and right that contribute to Jews' being by far the most targeted religious group for hate crimes for many years running.

These criticisms seem right to me. They're not flashy. They don't get the left the evil, racist, antisemitic Trump it so desperately wants...but they're hardly inconsequential.