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President Trump offered a preview last week of his 2020 campaign tactics, and they were ugly.

He intends to use the power of the presidency to harass his political opponents and create an air of scandal around them. By doing so, he hopes to make at least some voters believe that all politicians are equally corrupt rather than recognizing that Trump himself is the most corrupt president in a long, long time.

Specifically, Trump signaled that he might ask the Attorney General William Barr to investigate Joe Biden’s past dealings with Ukraine. In the same vein, Rudy Giuliani, Trump’s personal lawyer, said he wanted to ask Ukraine’s government for help in the investigation.

“On its face, there is nothing illegal here. Trump is leveraging his power as president to compel a dependent foreign government to smear the opposition party,” Jonathan Chait wrote in New York magazine. “It’s just something no president has ever thought to do before. The powers legally available to a corrupt president and a party that has turned a blind eye to his violations of governing norms may be more terrifying than anybody has considered.”