Democratic voters love bipartisanship. GOP voters do not. Republicans have learned to weaponize that asymmetry over the years. And sure enough, they're relying on it now to defend President Trump from impeachment.

Of course, Republicans want to appear as though they abhor partisan bickering and value compromise. We see this on display now, as Republicans argue that the impeachment of President Trump is a partisan sham.

"At the end of the day, the case isn't made," Rep. Doug Collins (R-Ga.) argued at the close of Monday's impeachment hearing in the House Judiciary Committee. "This is the first impeachment that is partisan on facts that are not agreed to."

Hugh Hewitt, the conservative radio host, last month wrote about "what looks to be the first purely partisan vote to impeach" and fretted about "the horrible precedent a purely partisan impeachment would set."

Last week, Senate Majority Leader Mitch McConnell (R-Ky.) thundered against the "rushed and partisan impeachment" taking place in the House.

This is an old trap. Republicans have spent years distorting the very ideas of compromise and common ground, setting bipartisanship as a goal for Democrats, but forever denying its fruition. The GOP has been using this tactic to win fights with Democrats at least since the very earliest days of Barack Obama's presidency.

Obama, you'll remember, came to national attention with a stirringly bipartisan speech in one of the most partisan settings possible: the 2004 Democratic National Convention. "We worship an awesome God in the Blue States, and we don't like federal agents poking around in our libraries in the Red States," he said. Four years later he became president.

Republicans quickly settled on a strategy: They would oppose every idea Obama had, every program and initiative — no matter how broad the appeal. Why? Because voters hate gridlock — and GOP strategists decided voters would blame president, even if he didn't deserve it.

"We're not here to cut deals and get crumbs and stay in the minority for another 40 years," then-Rep. Eric Cantor (R-Va.) said at the time. "We're going to fight these guys."

This required some wild contortions for the GOP. Obama dusted off a health-care plan that was hatched in a conservative think tank and had been passed by Republicans in Massachusetts, but couldn't sell it to their counterparts in Washington, D.C. McConnell voted for a bailout bill as the Great Recession started under President Bush — then tried to block its implementation under Obama. In 2012, McConnell even ended up filibustering a bill he himself had introduced, just to deprive Democrats of a victory.

It worked. ObamaCare passed Congress along partisan lines — and a few months later, Republicans won control of the House.

Given that history, Democrats should be leery of GOP appeals to bipartisanship. Even as they prepare to impeach Trump, though, they are are on the cusp of giving him a victory on his USMCA trade treaty intended to replace NAFTA. The benefits of the new agreement are in dispute, but "ratifying the agreement would also concretely help Trump as the 2020 election gets going," letting him boast of a rare bipartisan accomplishment, my colleague Ryan Cooper noted earlier this month. "It also goes without saying that the Republican leadership would never, ever, ever help Democrats in this way."

Indeed, that the Democrats would allow Trump a win in this environment seems crazy. "So, can someone explain to me why Dems appear about to sign on to Trump's USMCA trade deal?" liberal New York Times columnist Paul Krugman tweeted this week. "It's basically no change from NAFTA as is, but Trump will claim it as a triumph. Why give him that?"

But it makes sense when you remember that Democrats like the idea of compromise more than Republicans do. Polls consistently demonstrate this truth: A 2018 survey showed that 66 percent of Democrats favor compromise, compared to just 36 percent of Republicans. A 2017 poll put the split at 62 percent and 44 percent, respectively. The trend held even in 2010, when Obama held the White House.

The Democrats' misguided commitment to compromise and moderation can be seen in House Speaker Nancy Pelosi's (D-Calif.) fussing over the swing-district moderates in her caucus while progressives chafe. It's on display as former Vice President Joe Biden leads the Democratic presidential pack on an impossible promise to woo congressional Republicans. They understand that talking about compromise and moderation is the best way to generate support from their own voters. That may frustrate progressive activists, but elites like Pelosi and Biden want to win elections, and they think bipartisanship is their best shot. Meanwhile, President Trump may be able to win re-election, despite broad unpopularity, simply by trying to appeal only to his own base.

Given those trends, it isn't shocking that Pelosi tried so long to avoid impeachment. Actually, it's surprising she isn't doing more to seek a middle ground, like censure. But impeachment doesn't really lend itself to a bipartisan compromise — either Trump tried to subvert the 2020 election by pressuring Ukraine, or he didn't. It's that simple.

The evidence suggests Trump crossed the line. Officials said Monday night that the House will vote next week on two articles of impeachment against Trump. But Republicans won't vote for his impeachment, no matter how overwhelming the facts. They have their reasons. Don't be fooled. In the GOP's hands, pretending to care about bipartisanship is the most partisan act of all.

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