Donald Trump is starting to go after Sen. Bernie Sanders (I-Vermont). In a short attack video posted to Trump's Instagram account on Wednesday, Trump's campaign skewered the self-described Democratic socialist over his response to "Black Lives Matter" protesters who stormed the stage at a Sanders event earlier this year in Seattle. "The world is a dangerous place. We need a tough, strong leader in the White House. And it's not this guy!" the video's narrator says. "Bernie can't even defend his microphone — how will he defend the country?" the text block of the video reads.