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.

The video is another addition to what's becoming a signature Trump attack medium — Instagram. The latest featured familiar aspects, including footage of ISIS fighters, jocular stock music, and ad-hominem attacks on candidates' personality traits.

Trump has primarily focused his 15-second attack ads on perceived front-runners like Democrat Hillary Clinton and former Florida Gov. Jeb Bush (R). The reality television star's videos have mocked Bush's "low-energy" speaking style, as well as Bush's admission that he smoked marijuana.

For his part, Sanders has consistently used Trump as a rhetorical punching bag, skewering Trump's controversial statements about everything from immigrants living in the US illegally to The Des Moines Register publication.

On Tuesday night during the first Democratic presidential debate, Sanders threatened Trump with higher taxes in a theoretical Sanders administration.

"Well, let me tell you, Donald Trump and his billionaire friends under my policies are going to pay a hell of a lot more in taxes in the future than they're paying today," he said.

Watch Trump's video below:

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