It all started with Mitt Romney’s criticism of President Trump on Twitter yesterday:

When the only American citizen President Trump singles out for China’s investigation is his political opponent in the midst of the Democratic nomination process, it strains credulity to suggest that it is anything other than politically motivated. — Mitt Romney (@MittRomney) October 4, 2019

By all appearances, the President’s brazen and unprecedented appeal to China and to Ukraine to investigate Joe Biden is wrong and appalling. — Mitt Romney (@MittRomney) October 4, 2019

And of course Trump wasn’t about to let that go unchallenged, and he’s fired back several times today:

Somebody please wake up Mitt Romney and tell him that my conversation with the Ukrainian President was a congenial and very appropriate one, and my statement on China pertained to corruption, not politics. If Mitt worked this hard on Obama, he could have won. Sadly, he choked! — Donald J. Trump (@realDonaldTrump) October 5, 2019

Mitt Romney never knew how to win. He is a pompous “ass” who has been fighting me from the beginning, except when he begged me for my endorsement for his Senate run (I gave it to him), and when he begged me to be Secretary of State (I didn’t give it to him). He is so bad for R’s! — Donald J. Trump (@realDonaldTrump) October 5, 2019

I’m hearing that the Great People of Utah are considering their vote for their Pompous Senator, Mitt Romney, to be a big mistake. I agree! He is a fool who is playing right into the hands of the Do Nothing Democrats! #IMPEACHMITTROMNEY — Donald J. Trump (@realDonaldTrump) October 5, 2019

And to top it off, Trump said which former GOP senator was “better” than Romney:

No Kevin, Jeff Flake is better! https://t.co/IyENBffEjp — Donald J. Trump (@realDonaldTrump) October 5, 2019

That escalated quickly.

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Binders full of hacks: Media firefighters discover strange new respect for Mitt Romney after he criticizes Trump’s push for China to investigate Bidens