If you believe the New York Times, President Donald Trump hasn’t spoken to Senate Majority Leader Mitch McConnell in weeks, and their last phone call was an angry exchange that “quickly devolved into a profane shouting match.” While neither man commented on the record for the article, the information clearly came from sources close to McConnell, who conveyed the senator’s view that that president is unable to learn “the basics of governing,” as well as his worries that Trump is leading the Republican party to disaster.

After several months of off-and-on attempts to work with McConnell, it appears Trump is raising the stakes in their confrontation, with the state of Arizona being the site of what appears to be a looming proxy war. Trump’s endorsement last week of a gadfly activist’s primary challenge to incumbent senator Jeff Flake may have been the last straw for McConnell, as their simmering feud is now being fought in the open.

Tuesday night in Phoenix, Trump made clear his low opinion of the Senate and its leader. Though McConnell was mentioned directly only once — when Trump demanded that the Senate abolish the filibuster — there was little doubt that the rally’s enthusiastic chants of “drain the swamp” were directed at Republican rather than Democratic swamp-dwellers. The appearance was not so much an off-year election rally for Trump as it was the continuation of last year’s campaign against the leadership of the party that nominated him.