Late-night viewers were stunned Tuesday night by the sight of Stephen Colbert, Jimmy Fallon and Conan O’Brien all taking part in an opening sketch that hurled a slew of insults President Trump had thrown at various wee-hours hosts right back at him.

The spectacle could have been even larger.

Colbert worked the phones Tuesday in hopes of getting not only Fallon and O’Brien, but also ABC’s Jimmy Kimmel and TBS’ Samantha Bee to participate in the antics, according to a person familiar with the matter. The concept originated with Colbert and his team, according to three people aware of the process. “Colbert reached out to me this morning,” O’Brien told Variety via email on Tuesday night.  “I have since had my number changed.” Kimmel and Bee were unavailable, as their shows are on temporary hiatus. Many of TV’s late-night programs go dark around a major holiday like the Fourth of July.

Colbert’s plan broke with many of late-night’s conventions and spotlights a spirit of cooperation among the various shows that was rarely in evidence when wee-hours programming was dominated by Johnny Carson, then Jay Leno and David Letterman. There are more late-night hosts than ever before – and they don’t have to appear around midnight these days to be considered part of the format. In a dynamic that might surprise executives from a previous era, however, their bickering has diminished, not increased.

In a different era, Carson had little to do with competitors like CBS’ Pat Sajak or syndicated-TV’s Arsenio Hall. When Joan Rivers left her role as Carson’s substitute and accepted an offer from Fox  to launch “The Late Show Starring Joan Rivers” in 1986, Carson banned her from his “Tonight” and severed ties with her. She only returned to the program when Fallon took the seat. Likewise, Letterman and Leno never had much use for each other. After all, Leno took the “Tonight’ seat at NBC Letterman prized.  “I’ll be honest with you,” Letterman said during his last monologue on CBS in 2015. “It’s beginning to look like I’m not going to get the ‘Tonight Show.'” The two would team up only for a promo that aired during a CBS broadcast of the Super Bowl in 2010 – and even that played up their mutual distrust of each other.

These days, the hosts are all still locked in a battle for ratings – not to mention YouTube views, Facebook likes and (for a growing number) unique video streams. But they tend to support each other, rather than undermining a competitor.  When Michelle Wolf sparked controversy at the most recent White House Correspondents Dinner, Seth Meyers offered support for her on social media and elsewhere, even though Wolf – a former staffer on his “Late Night” on NBC – was about to launch a competitive series on Netflix. When Larry Wilmore stepped down from Comedy Central’s “The Nightly Show” in 2016, he spent part of his last week on air showing off gifts delivered to him from Samantha Bee and others. Colbert and Fallon ought to be at each other’s throats: Colbert’s overall viewership has risen since Trump was elected in 2016, while Fallon’s have fallen. Instead, the two have lent each other support. When Fallon kicked off his “Tonight” run in 2014, Colbert made an appearance in the debut show. When Colbert launched “Late Show” on CBS in 2015, Fallon turned up to return the favor.

This generation of hosts doesn’t have to act like Carson, who once lured an average of 9 million people to his program every night. He did it by keeping his politics to himself, not wearing them on his sleeve. With 14 different programs playing themselves out across CBS, NBC, ABC, Comedy Central, BET, TBS, Hulu, Netflix and HBO (and another one ready to launch on E!), the hosts need to dominate only a particular sliver of the populace to stand out. That means any rivalry among them has been tamped down. It also allows them to be more open about their feelings about any number of issues. With Trump castigating many of them, the hosts may see even more of a need to stick together.

Last night’s sketch shattered other standards, too. Both “Tonight” and “Late Show” used the bit to open their programs — a rare bit of cooperation between NBC and CBS that guaranteed more people would see the stunt. In the process, NBC gave Conan O’Brien prominent placement on a show he himself once hosted, and subsequently had to leave — a fact the network might not typically burnish.

In these heady days of late-night hosts acting in a new role of “Trumpire,” and with more viewers perusing their capers at times of their own choosing on various kinds of screens, it’s easy to imagine Colbert, Fallon, O”Brien and the rest of the group defying even more rules in the not-too-distant future.