I am always impatient with pundits and partisans who claim the current election is the most important of all time. However, we can't sell short how critical Tuesday's 2018 midterms have turned out to be.
On several fronts:
** Oversight: The apparent corruption and mismanagement by the president, the White House, and the executive branch are far more extensive than normal. That's why congressional oversight matters right now. But it's also the case that, especially in the House, the gap between what to expect from Democrats and Republicans is wider than ever. Over the last two years, Republicans haven't just ignored normal oversight; they've actively helped President Donald Trump attack the Justice Department, the FBI, and any other institution or person responsible for maintaining ethics in government. What's more, with a presidential election underway over the next two years, it's worth considering the serious possibility that a House run by the "lock-her-up" party would convene a special committee intent on slandering whomever the Democrats nominate in 2020. After all, that's essentially what Republicans did in 2016.
So both because there's so much oversight needed, and because the gap between what the parties would do is so wide, the difference on oversight between a very slim Democratic or Republican majority is a far more important consequence of the 2018 elections than it normally would be.
** Legislation: It's probably true that the 116th Congress, in 2019-'20, won't be among the most legislatively active no matter what happens in the midterms. But I wouldn't underestimate the possibility that continued unified Republican government results in important laws, especially because an election that allows Republicans to retain even a very slim House majority probably comes with an expanded Senate margin. The result could be that hard-liners get bills through the new Congress that failed in the 115th. On the other hand, while a Democratic House might mean gridlock, it's also possible that reducing the influence of the House Freedom Caucus could mean more compromise between the House, Senate, and president.
Don't forget, too, that legislation in the states is often even more important than federal laws, and midterms are even more important than presidential years because there are a lot more governors on the ballot. Whatever Congress does, these midterms are going to determine policies on education, health care, transportation, and taxation in the states. And there are a lot of contested big-state governor elections on the line.
** Nominations: Two more years of a Republican-majority Senate means a much stronger Republican influence over the judiciary; two years of Democratic-majority Senate will slow or stop Republican gains on the federal bench. Meanwhile, whichever party has the majority would use executive branch confirmations as a way to influence policy in the departments and agencies. All of that is normal - at least for any election where the Senate majority is up for grabs, as is the case this year.
** Future majorities: Whatever happens over the next two years, the results of this election will live on. In the Senate, of course, we're talking about six-year terms, so winning this year is crucial to winning majorities (and the size of those majorities) in 2020. Incumbency still matters, even if it's not quite as strong an effect now as it was in the 1970s and 1980s, so winning House seats in 2018 will help a party win those same seats into the future. What really gives this election particularly strong influence over the future, however, is at the state level. Governors elected this year will be in office for redistricting in big contested states such as Florida, Illinois, and Michigan. So will some state legislators; others will still need to be re-elected in 2020, but once again the winners this time will have an edge. And it's not just redistricting. The parties are strongly split on election rules right now, with most of the action in the states. This year's winners will have a stronger say in whether it becomes easier or more difficult to vote in state after state.
** Republican reactions: The idea that one midterm defeat will spur dysfunctional Republicans - let alone Trump - to step away from radicalism and return to Reagan-era conservative ideas and style is hopelessly naive. But imagine what would happen if Republicans do well this election. The party in general, and Trump in particular, will believe they are entirely bulletproof after upsetting the pundits and the polls once again. Those who counseled moderation and compromise will be proved wrong (or at least Republicans will believe the compromisers have been proved wrong, whatever the truth really is). And Trump himself will be vindicated, making it even more difficult for the party or anyone else to constrain him in any way.
Does that make 2018 the most important election ever? I won't argue that. But every general election is important. Midterm elections are perpetually underrated. And this one seems at least as important as normal, and probably somewhat more so.
Jonathan Bernstein is a Bloomberg Opinion columnist covering politics and policy. He taught political science at the University of Texas at San Antonio and DePauw University.