In theory, gaining single-party governance represents the apotheosis of partisan politics. In practice, it becomes a trap, with parties stuck between the impulse to promise too much and do too little. This eventually results in massive disillusionment among voters, and a loss of power for years afterward.

Democrats still haven't learned that lesson from their 2009-10 control of Washington. Republicans might get that lesson even more quickly.

The new age of Republican governance only began a little more than two months ago with the launch of the 115th Congress and the inauguration of President Trump. After one of the most unusual presidential campaigns in American history, many wondered what the next few years in Washington would look like. Could Trump find sufficient discipline to govern? Would it fall to Speaker Paul Ryan and Senate Majority Leader Mitch McConnell to run policy for the next four years?

Instead, the issue appears to be reversed. While the White House hit a few road bumps on messaging and comportment, their policy work has been focused on the campaign promises Trump made — at least as far as can be accomplished through executive action. Whether one agrees or disagrees with Trump's policies, it's clear that he intended to hit the ground running and make changes to the direction of government.

The problem in the early weeks of GOP control of Washington has come from the other end of Pennsylvania Avenue. The Republican House of Representatives has failed spectacularly in its first major effort — their seven-year promise to repeal ObamaCare. Not only did the failure to resolve internal differences on the American Health Care Act (AHCA) prompt questions about Republican capacity for governance, the way it failed made those questions even more pressing.

After all, Republicans had made ObamaCare repeal their top domestic issue not just in the previous election, but through four election cycles. Both Trump in 2016 and Mitt Romney in 2012 made it a top domestic agenda item as well. Through all of that time, Republicans had not come up with legislative language to effect a repeal. Most assumed they wanted to protect themselves from political attacks during a time when they lacked any real chance of winning on repeal, which makes sense politically.

That excuse expired on Nov. 8, 2016 — and yet the GOP struggled to put together a plan on which they could agree even among themselves for months afterward. Conservatives demanded a straight repeal, while moderates — and Trump — demanded a transitional plan to avoid throwing people off of their coverage. House and Senate Republicans had very different ideas of repeal and replace, again despite having seven years to settle these differences internally. Even after Republicans clearly had fallen into disarray in the final days of the AHCA effort, leadership insisted that dissent was nothing more than a negotiating tactic, and that they had the votes to win an ObamaCare repeal.

Instead, the GOP effort collapsed — and with it, part of their governing credibility. The latter doesn't just result from the aborted vote on AHCA, but the inability to have the Republican agenda ready on Day One. Glenn Reynolds rightly wondered in the aftermath why Republican leadership on Capitol Hill "didn't have bills lined up like airplanes on the runway." They certainly had enough advance notice on ObamaCare to prepare for the potential opportunity. Why were they so unprepared?

Republicans on Capitol Hill face two more immediate challenges to their credibility for single-party governance. Now that ObamaCare repeal has been derailed, President Trump wants to move to tax reform, another long-promised agenda item from the GOP. The path forward looks more direct, although it does not appear that this plane has come out on the runway yet, either.

Before they tackle tax reform, though, Congress must pass the rest of the FY2017 budget. The continuing resolution passed after the election runs out on April 28, at which point the government will shut down without new funding. Trump insists that the omnibus spending bill should include initial funding for his wall on the southern border — another longtime GOP promise — but opposition to that plan is also rising on both sides of the aisle.

Senate Democrats reportedly plan to filibuster the omnibus bill if it includes any funding for the wall. Even without the filibuster, the funding may not have enough Republican votes in the Senate, as John McCain (R-Ariz.), Jeff Flake (R-Ariz.), and John Cornyn (R-Texas) have all expressed significant reservations over the project. Some House Republicans are now opposed to it as well. Ryan and McConnell may have to kick that can down the road, too. Rep. Tom Cole (R-Okla.) told Morning Joe that the GOP needs to focus on the essentials in the omnibus plan. "To me," he said, "we ought to focus on the things we know we can do and we have to do."

While that may be the practical approach, it looks a lot like the failure to change the status quo on ObamaCare. That raises lots of questions about whether Republicans can actually achieve any of their agenda and govern effectively at the same time. If they can't deliver now, voters will assume they can't deliver at all — and this period of single-party governance may not last any longer than Democrats' in 2009-10.