President Donald Trump attacked democratic rival Joe Biden on Thursday at a campaign rally in Minneapolis, criticizing his career as both a senator and Vice President.

“He was never considered a good senator, he was only a good Vice President because he understood how to kiss Barack Obama’s ass,” Trump said to the crowd.

His comments about Biden came after he denounced his son, Hunter Biden, and again alleged a conspiracy between the father-son duo and the Ukrainian government.

Trump has previously asserted that Joe Biden used his political authority to influence the Ukrainian government to halt an investigation into a Ukraine-based gas company, of which Hunter was on the board of directors.

“Joe’s son Hunter got thrown out of the navy and then he became a genius on Wall Street in about two days,” said Trump.

However, Hunter Biden had significant finance experience before becoming “a genius on Wall Street,” having served as the executive vice president of the bank holding MBNA America, as well as serving in the United States Department of Commerce. Trump was correct in saying he was thrown out of the Navy, as he was discharged for failing a cocaine test.

“By the way whatever happened to Hunter, where the hell is he?” said Trump.

Trump went on to tell Hunter, “Your father was never considered smart.”

A Democratic-led impeachment inquiry into Trump is currently investigating whether the president used his position to pressure the Ukrainian government to investigate Joe and Hunter Biden.

Trump has consistently tweeted that the impeachment inquiry is a “witch hunt” by Democrats, and echoed these sentiments at the Minneapolis rally.

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“Democrats are on a crusade to destroy our democracy, that’s what’s happening,” said Trump. “We will never let it happen, we will defeat them.”