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There was a lot of breathless commentary in recent months about why Barack Obama hadn’t yet endorsed Joe Biden. Most of it was silly.

Obama’s non-endorsement should have been a non-story, because former presidents — or sitting presidents in their second term — rarely get involved in competitive primaries. In 2016, Obama did not endorse Hillary Clinton until June 9, after she had already clinched the nomination over Bernie Sanders. In 2008, George W. Bush didn’t endorse John McCain until all of the other leading candidates had dropped out. And Ronald Reagan didn’t endorse his own vice president, George H.W. Bush, until May 1988, when the nomination was effectively over.

Obama stayed true to this pattern by waiting to endorse Biden until his last rival — Sanders — had quit the race and Sanders himself endorsed Biden. Is there any takeaway from the endorsement, then? Yes: Obama went out of his way to signal that he agrees with the party’s shift toward a more progressive agenda. “I could not be prouder of the incredible progress that we made together during my presidency,” he said. “But if I were running today, I wouldn’t run the same race or have the same platform as I did in 2008. The world is different.”