In Washington, historical precedents should only be handled by trained professionals and the bomb squad. Nothing, aside from political timidity, has fostered more bad policies than the misremembering and misapplication of history. 

The 50th anniversary of the publication of the Pentagon Papers can serve as a reminder of how often the analogy of Neville Chamberlain appeasing Adolf Hitler in Munich in 1938 was applied to Vietnam. 

The Munich precedent, of course, was ludicrous since it failed to consider splits in the Communist world, the realities of Vietnamese nationalism and the minor detail that Ho Chi Minh was never planning on invading Poland as Hitler did in 1939.

Flawed history also plays a major role in domestic politics, although, of course, the results are far less cataclysmic. Right now, many Democrats, including some on Capitol Hill and in the White House, are adopting the wrong lessons from the political failures of Barack Obama in 2009 and 2010.

The new orthodoxy suggests that a key strategic mistake by Obama was embarking on lengthy negotiations over health care with Senate Republicans such as Chuck Grassley in the summer of 2009. Under pressure from Mitch McConnell, these Republicans would never have voted for Democratic legislation no matter how many GOP ideas were inserted into the bill. 

The supposed result: Democrats waited too long to approve Obamacare and lost their 60-vote filibuster-proof Senate majority. So the only escape route was for the House to pass word-for-word the flawed Senate version of the Affordable Care Act. 

Applied to 2021, the lesson is that the Democrats can’t waste a minute on Senate negotiations on infrastructure, voting rights or anything else. The trick is to slam everything through this summer — and somehow miraculously convince naysayers such as Joe Manchin and Kyrsten Sinema to kill the filibuster. 

What this glib version of history excludes are two names: Republican Arlen Specter and Democrat Martha Coakley.

Specter, a truly moderate, if somewhat devious, five-term Pennsylvania senator, had been castigated by his GOP colleagues for voting for the Obama stimulus package in early 2009. So Specter, unable to see a way to win a 2010 GOP primary, voted with his feet and became a Democrat that April. 

When Minnesota’s Al Franken was finally awarded his Senate seat in July after protracted electoral challenges, the Democrats found themselves strolling into the Emerald City with a 60-vote majority. It was the first time in more than three decades that either party had the votes to stifle a filibuster by merely holding its majority together. 

Even the sad-eyed death of Ted Kennedy in August 2009 did not dent Democratic dreams. Massachusetts Gov. Deval Patrick immediately appointed Paul Kirk, a former chair of the Democratic National Committee, to replace Kennedy as interim senator.

No one in the party initially worried about the special election in January 2010 to fill the seat since this was the Massachusetts of the Kennedys. 

But then no one imagined that the Democratic Senate nominee Martha Coakley would run the worst campaign of the 21st century, a debacle that still ranks up there with Jeb Bush’s hapless 2016 presidential bid.

Coakley’s misadventures as a candidate would have been comic if they were not so tragic for the Democrats. A portrait in overconfidence, Coakley disdained actually campaigning (mocking her GOP rival Scott Brown for shaking hands in front of Fenway Park in the cold) and sought warmth with a Caribbean vacation three weeks before the election. 

As a result, Brown won the election by 100,000 votes and the Democrats filibuster-proof majority vanished with a puff of wintry wind outside Fenway Park. 

What are the correct lessons to draw from this history?

While Manchin and Sinema give every sign of remaining loyal Democrats, the Specter precedent is a reminder that the constant demonization of senators in your own party can come with a lasting cost. In similar fashion, conservative Alabama Sen. Richard Shelby, scorned by the Clinton White House, abandoned the Democrats for the Republicans after the 1994 GOP congressional sweep.

The other moral is trickier. 

The biggest resistance to Obamacare came from wavering Democrats such as Nebraska Sen. Ben Nelson and endangered incumbents such as Arkansas Sen. Blanche Lincoln. Without their votes to cut off a GOP filibuster in late 2009, the Affordable Care Act would have died on the operating table.

Even though the glacial pace of negotiations with Senate Republicans did not produce a single vote for Obamacare, it did convince moderate Democrats that a sincere effort had been made to craft bipartisan legislation. 

In many ways, the same thing is happening with infrastructure in the Senate this week. If a bare-bones bill can attract 10 Republican votes to surmount a filibuster, then the Senate will have demonstrated that it can legislate, even in this bitterly partisan era. If bipartisanship fails, all 50 Democrats are likely to support an ambitious infrastructure bill under the reconciliation process.

What activists and, yes, some White House aides fail to understand is that legislating usually takes time. 

Legislative majorities in a nation as varied and as unruly as America rarely move in total lockstep fashion. The kind of speed associated with Franklin Roosevelt’s One Hundred Days and Lyndon Johnson’s civil rights triumphs was only possible because of overwhelming congressional majorities.

That’s why Democrats should maintain a sense of realism about what is possible with skin-of-your-teeth margins in both chambers of Congress. The party has already made the best political case possible for the 2022 elections with the passage of the $1.9 trillion economic stimulus and with the pandemic receding at a staggering pace.

Patience is an underappreciated virtue in politics. But at a time when Democrats veer from euphoria to despair on an almost hourly basis, there is a lot to be said for playing the waiting game.

Walter Shapiro has covered the last 11 presidential campaigns. He is also a fellow at the Brennan Center for Justice at NYU and a lecturer in political science at Yale. Follow him on Twitter @MrWalterShapiro.