President Trump, shown here in November 2016 with then-president Barack Obama, has made Obama and Hillary Clinton regular foils during his early months in office. (Jabin Botsford/The Washington Post)

He boasted of besting Jeb Bush in the Republican primary campaign for months after the former Florida governor had left the race. Even after securing the Republican Party’s nomination, he would rattle off his vote tally, noting how it dwarfed the performance of Ohio Gov. John Kasich.

And now nearly three months into his presidency — and more than five months after the election — Trump continues to relive his political victory over Hillary Clinton and her allies.

The counterpuncher in chief finds himself looking in the rearview mirror in search of sparring partners, repeatedly settling on Clinton, former president Barack Obama and others from the long-finished campaign.

No one within earshot of the president in recent months has gone long without hearing about his electoral college victory over Clinton. And on Syria policy, the economy, infrastructure investments and the ongoing probe over his campaign’s ties to Russia, Trump has used Obama and his aides as foils for his administration.

“One of the president’s best strategies is to have a straw man,” said former Trump aide Sam Nunberg. “It’s very good for the base.”

(The Washington Post)

Even as Trump is basking in one of his best political moments following his decision to authorize airstrikes against Syrian President Bashar al-Assad, Trump on Wednesday singled out his predecessor for criticism in a Fox Business News interview — despite repeatedly advising Obama not to use military force in the past.

“What I did should have been done by the Obama administration a long time before I did it,” Trump said, while perched in an ornate chair at the White House. “I think Syria would be a lot better off right now than it has been.”

[Has Trump become the ‘don’t blame me’ president?]

The remark is just one in a series of comments in which Trump has sharply criticized the former president’s foreign and domestic policy, even leveling the unsubstantiated claim that Obama ordered a wiretap of Trump Tower during last year’s presidential campaign.

The pattern breaks a tradition of presidents taking a forward-looking approach to their presidencies.

“In terms of the etiquette of the presidency, it’s very poor form,” said Stephen Hess, a presidential scholar at the Brookings Institution. “Presidents by and large don’t do this.”

He added that Trump “simply can’t get over his infatuation with the Obamas and the Clintons.”

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But Trump supporters say the president is simply taking a page out of Obama’s playbook. Years after the worst of the economic recession had passed, Obama frequently castigated Republicans for driving the economy “into the ditch.” But even with that well-worn line, Obama rarely criticized former president George W. Bush by name.

And former Obama aides note that he did, in fact, inherit an economy in a tailspin in early 2009, compared with the steady job growth and low unemployment rate inherited by Trump.

“First and foremost, Obama was accurate in his descriptions and Trump is most decidedly not,” said Dan Pfeiffer, who was a former senior adviser to Obama. “There is an important tradition of presidents’ trying to pull the country together after elections, and Trump has tried to do the opposite by continuing to re-litigate the election.”

During the presidential campaign, few issues would rouse Trump’s supporters like Clinton and Obama. In front of a screaming mass of thousands, he criticized Obama for being weak on the world stage and regularly accused Clinton of breaking the law with her use of a private email server, prompting chants of “Lock her up!” from the crowd.

As president, Trump has changed little in that regard.

“She was guilty on every charge,” Trump said of Clinton in the Fox Business interview. “[FBI Director James] Comey was very, very good to Hillary Clinton, that I can tell you. If he weren’t, she would be, right now, going to trial.”

Trump has also pointed the finger at Obama, his aides and government staffers held over from the previous administration for damaging leaks and delays in moving his agenda forward. Most recently he has had former Obama national security adviser Susan E. Rice in his crosshairs, accusing her of using surveillance tools for political purposes; she has adamantly denied the allegation.

[President Trump’s thoroughly confusing Fox Business interview, annotated]

For a president who counts winning among the most important and constant things in his life, his unexpected electoral college win over Clinton has become a high-water mark for his political career — especially with few clear victories during the early months of his presidency.

“The electoral college is very, very hard, they say almost impossible for a Republican to win. The odds are stacked,” Trump told union members at a conference in Washington last week. “They’re saying there’s no way to 270. Well, but there was a way to 306.”

Trump often pitches the American people on his policies by framing them in opposition to those of his predecessor. At a recent meeting of CEOs in the White House, Trump contrasted his goal of implementing ready-to-go projects with infrastructure spending in Obama’s stimulus bill.

“You know, there was a very large infrastructure bill that was approved during the Obama administration, a trillion dollars,” Trump said at a CEO town hall this month. “Nobody ever saw anything being built. I mean, to this day, I haven’t heard of anything that’s been built.”

While Trump claimed Obama spent infrastructure funds on “social programs,” the largest chunk of spending dedicated to infrastructure in Obama’s 2009 stimulus package — more than $26 billion — went to highway infrastructure programs.

Trump’s comments reflect a backward-looking approach to establishing Trump’s presidential legacy, Hess said.

“Is your legacy defined by your predecessor? By your enemies?” Hess noted. “Presidents look ahead. Why would a president spend so much time looking back?”

Nowhere has Trump’s focus on Obama been more acute than on Syria. In recent days, Trump has pointed to Obama’s failure to enforce his “red line” against the use of chemical weapons by Assad.

Yet in June 2013 — after a deadly chemical weapons attack in the Damascus suburbs — Trump repeatedly praised Obama for not taking military action. In a tweet on June 15, 2013, Trump wrote: “We should stay the hell out of Syria, the ‘rebels’ are just as bad as the current regime. WHAT WILL WE GET FOR OUR LIVES AND $ BILLIONS? ZERO.”

On the campaign trail, Trump continued to oppose any involvement in Syria and accused Clinton and some of his Republican opponents of wanting to start World War III.

Even among Obama critics in the Republican Party, Trump’s focus on the past has little sway.

“I don’t think it’s a secret that I disagreed with many of the decisions made by the Obama administration on foreign policy, but that presidency’s over,” Sen. Marco Rubio (R-Fla.) said at a news conference last week. “We have a new presidency.”