MONACA, Pa. — President Trump’s appearance on Tuesday at the site of a multibillion-dollar chemical plant under construction here was ostensibly about energy policy.

Instead, the crowd of mostly white, male workers in bright orange and yellow construction vests was the audience for a 67-minute speech that was nearly indistinguishable from something that Mr. Trump would deliver at one of his campaign rallies.

Mr. Trump railed against China, President Barack Obama, the lawsuits he is facing, the money he claims being president has cost him, Hillary Clinton, Democrats running against him and, as always, his news coverage.

The president occasionally touched on energy policy as he claimed credit for one of the largest active construction projects in the United States, the Shell Pennsylvania Petrochemicals Complex. The plans for the complex, which will convert natural gas into plastics, were in fact announced in 2012, while Mr. Obama was in office.