Of Course Trump is to Blame
He assigned the bomber his target list. Essentially every person targeted by the bomber had been targeted by Trump lies and abuse. Trump wasn't alone, of course, all his lies were repeated and amplified by Fox Lies and the right-wing radio and social media freak shows - but something said by the President carries a lot more moment than the even the rantings on Fox. Trump is not innocent in the Pittsburgh and Kentucky murders either. Despite his Jewish Son in Law and family, he has trucked often in anti-semitic and other racist tropes, as well as giving comfort to various Neo-Nazi groups. Equally important, he devotes his public speech to dividing Americans and fulminating hatred among them.
Trump, though is anything but sui generis. He is the organic product and natural culmination of the modern Republican Party as created by Richard Nixon, Roger Ailes, and Lee Atwater - a party created out of racism, fear, and envy. Maureen Dowd notes that Ailes, whose other poisonous creation was Fox News, was a student of Hitler's propagandist Leni Riefenstahl, so it's no surprise that many of Trump's tactics, like Ailes', come right out of the fascist playbook, especially in his repeated resort to the Big Lie and demonization of minorities.
The scary thing is that modern American has acquired such a potent appetite for this truly disgusting human being: corrupt, decadent, a molester, draft dodger, and a scam artist. Of course he has the cover of his party, who after early opposition cowered into line, almost without exception. Even David Brooks, a NYT columnist nominally opposed to Trump, wrote a column disgracefully declaring himself "An American Nationalist." The content of the column was anodyne, but Brooks, with his elite education surely knows that choosing the word "Nationalist" over "Patriot" was waving a red flag in front of the White Nationalist and Neo-Nazis. You too, Mr. Brooks, have some of the blood of Pittsburgh on your hands.