House Speaker Paul Ryan’s biggest nightmare just became reality: His party’s divisions defeated his party’s own agenda.

The GOP’s factions turned Ryan's first big governance test since his party won control of Congress and the White House in November into an enormous flop, and it deflated the party’s central campaign promise to repeal and replace Obamacare. After years of disagreement on how to oppose the Democratic White House, the party is just as divided in how to lead with a Republican White House.

“Moving from an opposition party to a governing party, comes with growing pains and well, we’re feeling those growing pains today,” Ryan said Friday afternoon announcing the bill was being pulled, with palpable frustration at the party whose votes he failed to wrangle.

“Ultimately, this all kind of comes down to a choice: Are all of us willing to give a little to get something done?” the Wisconsin Republican continued. “If we’re willing to do that, we still have such an incredible opportunity in front of us. There remains so much we can do…that’s why I’m here.”

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But Ryan is facing the stark reality that’s plagued his predecessors for decades: Leading a polarized body makes getting anything big done increasingly near impossible and makes the Speakership the most thankless job in Washington.

It’s why Ryan didn’t want the post in the first place. He spent weeks deflecting suggestions he might seek it. Later, as he agreed to step up, Ryan demanded party unity, telling members he wouldn’t take the job unless he was supported by everyone — from the conservative Freedom Caucus to the moderate Tuesday Group, both of which, it turns out, struggled to get on board with the healthcare bill for different reasons.

Ryan's immediate predecessor, House Speaker John Boehner, resigned from Congress in the middle of his term amid far-right efforts to oust him. Boehner had already lived through one unpopular government shutdown that he’d spent months trying to avoid and, days later, he did a deal with Democrats to fund the government that would likely have cost him his Speakership had he not already given it up.

And the same far-right, tea party wave of Republicans that made Boehner's life miserable includes many of the same representatives — and the Freedom Caucus — who balked at the House bill.

“You’ve got a group of Republicans who don’t know how to say yes,” former Virginia Republican Rep. Tom Davis said. “They are a great opposition party. They’re great at ripping the other side apart, but they can’t get to yes.”

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Davis said Ryan’s choices are limited. He can try to get the Freedom Caucus to take their “ideological blinders” off or move to the middle and try to work with moderate Democrats.

But, he added, after Friday, things aren't looking great for Ryan or the House GOP>

“It makes them look incompetent, it makes them look like the gang that can’t shoot straight," he said. “The problem (for Ryan) is the Democrats smell blood in the water.”