Opinion: Obama signals his intent to fight Trump to the end

Reporting from Philadelphia â€”  “There’s not a liberal America and a conservative America,â€� Barack Obama said in his first Democratic convention speech, exactly 12 years ago tonight, in Boston. “There’s the United States of America.â€�

Obama didn’t repeat those lines in his long and plaintive sermon to Americans at this year’s convention. He knew they wouldn’t work in a year of unusual division and rancor.

But that audacious assertion of unity was still his central theme: An insistence that America, and Americans, are in better shape than they look — kinder, tougher, and perfectly capable of solving our problems cooperatively, without top-down direction from a “homegrown demagogue.�

“America is already great,� the president insisted. “America is already strong. And I promise you, our strength, our greatness, does not depend on Donald Trump.�

It’s unusual for a retiring president to go on the offensive so bluntly and against one of the candidates running to succeed him. A traditionalist might consider it unbecoming. In 2008, for example, George W. Bush never talked that way about Barack Obama.

But Obama not only holds Trump in contempt (he’s often ridiculed him before); he clearly views the Republican nominee as a direct threat to his legacy. Not merely the political legacy of his economic stimulus, his healthcare law and his energy projects, but — more important — the legacy of his battered but still lovely 2012 dream of One America.

In principle, Obama’s job at the convention was to defend his own record, endorse Hillary Clinton and persuade voters who helped him win the White House that she’s a worthy successor.

He did all those things — but he also made it clear that he feels as if he’s running against Trump too. Clinton’s campaign aides say they hope he’ll campaign for her vigorously this fall. Judging by Obama’s speech, they’re about to get their wish.

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