As they begin the road to recovery, Democrats are super eager to stress that they will not—indeed, cannot—settle for just being anti-Trump. To be sure, say strategists and staffers, the party will fight furiously against Republican policies that conflict with their values. (Resist!) But if President Trump embraces a progressive idea—such as, say, serious infrastructure reform—the Democrats will be happy to engage.

Being a reflexively obstructionist Party of No is not the way to win back voters, they tell me. Democrats must stand for something. They need a compelling governing vision that can be clearly conveyed, preferably in pithy TV ads and bumper-sticker slogans.  

Which all sounds impressively proactive and high-minded—and in no way relevant to the coming election cycle.

Presidential candidates need a vision. Donald Trump certainly had one—no matter how dark, divisive, and fundamentally untethered from reality. (For the 40,000th time: The man has no chance of saving the coal industry. Zero.) But when it comes to midterm elections, the “out” party’s mission is not to spotlight how awesome its ideas are but rather to kick the crap out of the guy in the Oval Office, his ideas, and all of his legislative enablers.   

“Parties like to develop a positive agenda to prepare for their next turn at governing, and this is a good and useful exercise,” noted Larry Sabato, who heads the Center for Politics at the University of Virginia. “But in midterm elections, the voters are usually just reacting to the incumbent president—and almost always negatively.”

Sabato ran through a litany of midterm outcomes from the past six decades, including Democratic wins in 1958 (“Ike’s poor economy”), 1974 (“anti-Watergate, anti-Nixon pardon”), and 1982 (“Reagan’s poor economy”), and Republican wins in 1966 (“anti-Vietnam War, Great Society backlash”), 1994 (“Clinton’s poor economy and controversies”), and 2010 (“anti-Obamacare, continuing poor economy”). “In every case, for each party,” said Sabato, “victory wasn’t delivered on account of a terrific positive platform but because of a negative reaction to the policies and actions of the incumbent president and/or Congress.”

If anything, this trend has gathered steam in recent years as congressional races have grown ever more nationalized. Certainly, Obama-era Republicans offered a master class in the political efficacy of being “anti.” The current House majority was explicitly built on fear and loathing of the 44th president. Senate Leader Mitch McConnell, meanwhile, elevated legislative obstructionism to high art, most vividly showcased by his nearly year-long refusal to consider Supreme Court nominee Merrick Garland.

Democrats busted their humps trying to make Republicans pay for their gridlocking. But, for all voters’ grousing about congressional dysfunction, they rarely bother punishing lawmakers for not playing nicely. Indeed, the quickest way for a GOP legislator to get booted under Obama was to be labeled a compromising squish.

“One thing we can take from the past several elections is that political obstructionism does not have the political price many people thought it did,” observed a Democratic Senate aide.

While nobody does obstructionism like McConnell, House Democratic leader Nancy Pelosi has a keen appreciation of the value of just saying no. In early 2005, a freshly reelected George W. Bush was hot to overhaul Social Security. Republicans held the White House and both chambers of Congress. They had the vision. They had the numbers. What could possibly go wrong?

Everything. Even thinking about messing with entitlements is politically fraught, and Pelosi decided to make Bush bleed for it. For months, she kept her troops focused on beating the bejesus out of Bush’s proposal, driving public support for it down, down, down. The negativity became so relentless that some Democratic members began to get twitchy. When would the caucus move beyond slamming Bush and put forth a reform plan of its own? Famously, Pelosi’s stock response became: “Never. Does never work for you?”

By spring, Bush’s plan was deader than disco—and stayed dead despite his efforts to revive it, which ran right through the 2006 midterms. That November, Democrats retook both chambers of Congress in a wave election that startled pretty much everyone.

This is not to suggest Bush’s Social Security bellyflop prompted the Democrats’ electoral sweep (though denying the president a key policy win did aid the cause). Broadly, 2006 was a referendum on Bush 43’s job approval, which had taken a major hit thanks to his shabby handling of Hurricane Katrina and, more importantly, his Iraq war folly. Democrats beat those drums hard. They also spotlighted a string of nasty scandals plaguing congressional Republicans during that period. (Anyone recall Mark Foley’s penchant for teenage House pages?)

And so Democrats carried the day, despite having put forth nothing remotely approaching a grand governing message, or even a cohesive brand identity. As Time magazine noted at the time:

Democrats won't be taking over control of Congress with a blueprint for how to capture the biggest prize, the presidency in 2008. The reason is simple: apart from the fact that they faced an unpopular President and an unpopular ruling party both blamed for a very unpopular war, the Democrats already can't agree on why they won.

As it so often the case in such cycles, they did not need to.

“You always have to tell voters what you’re for,” said Drew Hammill, deputy chief of staff to Pelosi. That said, he acknowledged that it is a question of priorities. “The mid-term is typically a referendum on the president. When you’re in the opposition, you want to take his numbers down before you start talking about anything positive.”

Pelosi has long used a “Tylenol versus Advil” analogy to explain the imperatives of negative branding, said Hammill. “She points out that, when you look at a Tylenol or Advil commercial, they are always attacking each other. There is usually a specific mention of the other brand.” Once you’ve decimated the competition, said Hammill, “then you talk about what is good about yourself.”

So, sure, Democrats will want to work a little on that whole identity crisis. (Not that Republicans dealt with theirs last cycle.) “The entirety of the Democratic vision for 2018 and 2020 cannot be simply, We are not Donald Trump,” insisted the Senate aide.  

But, for now at least, the party shouldn’t expend too much time or energy fretting about the big picture. Nothing mobilizes voters like an inspirational enemy, and in Trump, Democrats have found themselves a world-class one.

In midterm politics, as in pain relief, rule No. 1 is to destroy the other guy’s credibility. You can sort the rest out later.