WASHINGTON ― Michelle Obama is an indomitable force on the campaign trail for Hillary Clinton, and the Democratic nominee has Donald Trump to thank for that.

At a fundraiser for Clinton in La Jolla, California, on Monday, President Barack Obama said his wife is campaigning harder than ever because Trump is the Republican nominee for president.

“Some of you may be aware of the fact that Michelle does not really love politics,” Obama said to laughter at the event. “But the passion that she’s brought to campaigning this time speaks to the degree that this election is different, the choice is different.”

No matter how much he disagreed with his opponents, Sen. John McCain (R-Ariz.) in 2008 and Mitt Romney in 2012, Obama said he always considered them “honorable people.”

“I wasn’t concerned about the Republic if they had won,” Obama said. “And so part of the reason Michelle is working the way she is, is because she understands, as I understand, that some more fundamental values are at stake in this election. It has to do with our basic standards of decency ― how do we treat people.”

Two weeks ago, Michelle Obama delivered an emotional speech about a hot-mic recording of the Republican nominee bragging about groping women.

“This was a powerful individual speaking freely and openly about sexually predatory behavior and actually bragging about kissing and groping women,” she said. “It is cruel. It is frightening. And the truth is, it hurts. It hurts.”

Trump held back for a while, but finally lashed out at the first lady late last week.

“We have a president. All he wants to do is campaign. His wife ― all she wants to do is campaign,” Trump said. “And I see how much his wife likes Hillary. But wasn’t she the one that originally started the statement, ‘If you can’t take care of your home’ ― right? ― ‘You can’t take care of the White House and the country?’”

The Obama campaign denied at the time that his wife’s statement about family values was about Clinton.

For the first lady, Obama said on Monday, the election comes down to this: “Do we treat people who are of a different faith as part of the fabric of America, or do we label them as something foreign, not a ‘real American,’ and thereby subject to different standards when it comes to how our laws apply?”

And this: “Do we think of women as equal and full citizens, capable of doing anything, or do we think of them as objects of either scorn or lust or our own satisfactions?”

“Do we think that government is something serious, that we have an obligation to make sure that to the best of our abilities we leave the country a little bit better off than how we found it, or do we think that it’s an infomercial or a reality TV show,” Obama continued.

In the end, he said, “Michelle’s conclusion is, is that we can’t have [Trump] in the Oval Office.”

Editor’s note: Donald Trump regularly incites political violence and is a serial liar, rampant xenophobe, racist, misogynist and birther who has repeatedly pledged to ban all Muslims — 1.6 billion members of an entire religion — from entering the U.S.