President Trump fired off a series of Russia related tweets on Sunday, July 9. Here's what you need to know. (Monica Akhtar/The Washington Post)

On Sunday morning, President Trump spoke of his new alliance with Russian President Vladimir Putin to erect an “impenetrable Cyber Security unit so that election hacking, & many other negative things, will be guarded.”

This, the president tweeted at 7:31 a.m., came after Putin “vehemently denied” interfering with the 2016 U.S. election.

The tweet's timing could not have been more perfect — for congressional critics of Trump's new plan.

It gave them just enough of a head start to workshop one-liners and practice their comedic timing before the Sunday morning political talk shows.

Sen. Lindsey O. Graham (R-S.C.) quipped on NBC's “Meet the Press” that Trump's plan was “not the dumbest idea I've ever heard, but it's pretty close.”

Graham called Trump “literally the only person I know of who doesn't believe Russia attacked our election in 2016" and said he was “dumbfounded.” Graham said Trump is “hurting his presidency by not embracing the fact that Putin is the bad guy.”

Washington weighs in on President Trump's visit to theGroup of 20 summit in Hamburg, and whether he believes that Russia meddled in the 2016 presidential election. (Victoria Walker/The Washington Post)

A quick primer: Many, many people and several U.S. government intelligence agencies have accused Putin and Russia of interfering in the 2016 election to help Trump.

A special counsel has been appointed to lead the Justice Department's probe into the Trump campaign's possible Russia ties. There's also a criminal probe and congressional fact-finding investigations, all examining Russia.

Yet on Sunday, of the 193 countries Trump could have partnered with on cybersecurity, he chose Russia.

The irony was not lost on members of Congress.

Sen. John McCain (R-Ariz.), speaking on CBS's “Face the Nation,” deadpanned: “I am sure that Vladimir Putin could be of enormous assistance in that effort since he’s doing the hacking.”

McCain said “there has been no penalty whatsoever” for Russia's interference in the U.S. election — or in other countries.

Sen. Marco Rubio (R-Fla.), who has been a Trump critic since they faced off in the GOP primaries last year, tweeted comparisons to other partnerships that would appear doomed from the start.

The criticism — and claims of confusion — spanned both sides of the aisle.

Rep. Ruben Kihuen (D-Nev.) retweeted a statement from Nikki Haley, the U.S. ambassador to the United Nations: “We can't trust Russia and we won't ever trust Russia.”

And other legislators chimed in:

And the quips and criticism weren't coming from politicians alone. Preet Bharara, the former U.S. attorney in Manhattan whom Trump fired in March, took the president to task for his statements about Putin's denials.

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