When Barack Obama took office in 2008, one of the most difficult things for conservatives was the fact that he soon had a compliant and Democrat-controlled Congress to do his bidding. With the defection of Arlen Specter in April of 2009 and the seating of Al Franken as a result of the disputed Minnesota senatorial race, the Republicans lacked even the 41 votes necessary to stop the Democrats in the Senate, although they finally gained exactly that number with the surprise election of Scott Brown of Massachusetts.

However, after that point, the Republicans in Congress were able to stop some of the Obama agenda after gaining the ability to muster at least 41 votes in the Senate, and after they gained the House in 2010. That’s why the Democrats in the Senate triggered the nuclear option for judicial appointments in November of 2013, when they still controlled both the presidency and the Senate but the Republicans had gained enough senators to block judicial confirmation under the old (non-nuclear) rules. But under the new nuclear option rules (see this for a full explanation of how it works), a simple majority of Democrats could successfully force a vote to confirm Obama’s judicial appointments, rather than needing to gain 60 votes to close down debate.

After the GOP took control of the Senate in 2014, the nuclear option ceased to be as helpful for the Democrats because the GOP majority could now block Obama’s appointments (which they did, for example, in the case of Obama’s attempt to put Garland on the Supreme Court). And it was not just Garland they stopped, either; there were others.

Not everyone remembers all of this Senate history. But for those who do remember it, it probably came as no surprise when Harry Reid mentioned recently that the next Senate will probably re-activate the nuclear option for judicial appointment confirmations, and when Hillary’s running mate Tim Kaine repeated the idea last Friday. Most Americans who don’t follow the details of politics probably don’t pay attention to the ins and outs of this sort of thing, but the bottom line is that the motivation for the dominant party to activate the nuclear option comes into play mainly when a president and Senate are controlled by that same party, but when the opposition party also has at least 41 votes in the Senate.

That’s one of the reasons why the question of which party controls Congress is exceedingly important; gridlock can be a very good thing when a president whose agenda you distrust and/or fear has been elected. And that’s why the possibility of Trump’s negative coattails in 2016 looms large. If Hillary Clinton becomes the next president and the Democrats take control of the Senate with the GOP retaining at least 41 seats, that would set up a situation in which the nuclear option for judicial appointments could once again come into play.

What about the Democrats using the nuclear option for legislation other than approval of judicial appointments? Reid didn’t mention that, but his forbearance on that score probably comes from the fact that the Democrats are not projected to take the House this year. Without control of the House, it probably wouldn’t do the Democrats much good to exercise the nuclear option in the Senate for issues other than judicial appointments, because most legislation needs to be approved by both houses of Congress. The reason the nuclear option for judicial appointments is especially tempting is that judicial appointments are confirmed by a vote in the Senate only.

It should be clear why the situation in which Hillary Clinton would be president and both houses of Congress would be in Democratic hands is to be very much feared. If that were the case, the Democrats might even decide to invoke the nuclear option not just for judicial appointments but more generally, in order to maximize Democratic power to do things without interference from the 41+ GOP senators.

All of this further drives home the fact that, whomever you choose to vote for at the top of the ticket, it is exceedingly important to go to the polls on Election Day and vote for Republicans in Congress. And it also explains why Ted Cruz has been busy saying that a Republican Senate could and would continue to block any of Hillary’s SCOTUS appointment, just as they did after the 2014 election with Obama’s.

In summary, it is of the utmost importance that the GOP holds the House, which it seems likely to do. But the Senate outlook is very iffy—so please make sure to vote and not stay home.

[Neo-neocon is a writer with degrees in law and family therapy, who blogs at neo-neocon.]