“You’ll regret this, and you may regret this a lot sooner than you think.”

That was my warning to Senate Democrats in November 2013. Their leader, Harry Reid, had just persuaded them to trample longstanding Senate rules and precedents. Now that some Democrats are proposing further radical changes to the Senate’s functioning, it is instructive to recall what happened next.

To confirm more of President Barack Obama’s controversial nominees, Democrats took two radical steps. First, since the nominees had proved unable to earn the 60 votes necessary to overcome a filibuster, Democrats sought to change Senate rules so that ending debate on most nominations would require only a simple majority. Second, lacking the two-thirds supermajority needed to change the rules normally, Democrats decided to short-circuit standard procedure and muscle through the new rule with a simple majority as well — the first use of the infamous “nuclear option.”

Republicans opposed both moves on principle. Strong minority rights have always been the Senate’s distinguishing feature. But when appeals to principle fell on deaf ears, I tried a practical argument. The political winds shift often, I reminded my Democratic friends. I doubted they’d like their new rules when the shoe was on the other foot.

Unfortunately, Senate Democrats bought what Senator Reid was selling — but buyer’s remorse arrived with lightning speed. Just one year later, Republicans retook the majority. Two years after that, Americans elected President Trump. In 2017, we took the Reid precedent to its logical conclusion, covering all nominations up to and including the Supreme Court.