Barack Obama returned to the campaign trail in Michigan over the weekend and laid an irresistible political trap for Donald Trump. The former Democratic president mocked his Republican successor for lavishing attention on renovations and interior design instead of his presidential responsibilities.

“I don’t know if you’ve noticed, but he seems very focused on home renovations. He should be on HGTV,” Obama said.

“The guy’s building a ballroom that’s bigger than the White House. He’s paved over the Rose Garden, put a helicopter pad on the South Lawn.”

“And there’s gold everywhere. What’s up with the gold?”

“He’s got the White House looking like Saddam Hussein opened a Cheesecake Factory. Just gold everywhere.”

The remarks drew hearty laughter, and the joke carried a pointed criticism. Trump has focused heavily on remodeling and renovations as his presidency has struggled, while his taste has filled the Oval Office with gold curios.

Obama’s mockery gave Trump an obvious opportunity to shift the conversation. He could have highlighted other concerns, offered a constructive message and attempted to show that the former president’s criticism was misplaced.

Instead, Trump spent much of Monday demonstrating exactly why Obama’s joke landed. Rather than moving past the ridicule, the president repeatedly returned to his renovation projects and defended them in striking detail.

Before leaving for Mississippi, Trump held a seven minute question and answer session with members of the White House press corps. More than half of that exchange was devoted to his complaints about Obama’s remarks.

The president later appeared at a rally supporting struggling GOP Sen. Cindy Hyde-Smith. There, Trump spent another six minutes responding to the Cheesecake Factory joke and attacking the Democrat who delivered it.

Trump called Obama “a stupid person” and “a lousy president.” He also claimed Obama “doesn’t like” companies such as the Cheesecake Factory, an argument that did little to address the actual substance of the ridicule.

The Republican additionally insisted that he had spent “peanuts” on renovations to the White House. That description sat awkwardly beside roughly $1 billion in investments associated with those projects.

Trump also wanted Americans to know that the work had involved the world’s “finest artisans.” He said the effort was intended to make the presidential mansion “beautiful,” further extending a public discussion centered on the renovations Obama had just mocked.

The president did not address Obama’s reference to Saddam Hussein. The comparison formed the sharpest edge of the former president’s description of a White House covered in gold.

Obama’s argument was not merely that Trump likes gold or enjoys redesigning historic spaces. His broader criticism was that Trump appears preoccupied with vanity projects while holding an office burdened with far more important responsibilities.

Trump’s response only sharpened that contrast. Given repeated chances to change the subject, he instead devoted significant portions of two separate appearances to defending his decorating choices, praising the people involved and insulting Obama.

That was the trap Obama set, and Trump stepped directly into it. A joke about the president’s inability to look beyond gaudy renovations prompted the president to spend even more time talking about those same gaudy renovations.

Trump’s reaction also kept Obama’s Cheesecake Factory line alive well beyond the Michigan campaign appearance. Each complaint and boast returned attention to the gold, the ballroom, the Rose Garden, the helicopter pad and the scale of the investments.

The result was a self inflicted political spectacle. Obama suggested that Trump’s priorities were badly misplaced, and Trump answered by making those renovation priorities the center of his own public comments.

Rather than disproving the criticism, Trump supplied its most vivid supporting evidence. His defensive fixation transformed Obama’s punchline into a demonstration, with the president enthusiastically making the former president’s case for him.