When President Trump backtracked (slightly) from controversial remarks he made on Monday in which he questioned the U.S. intelligence community’s conclusions that Russia interfered in the 2016 U.S. election, I wasn’t surprised. It was another demonstration that what usually forces Trump to back down from a confrontation or concede defeat is not just the intensity of opposition (particularly if it’s coming only from congressional Democrats), but the breadth of that opposition: Trump usually feels compelled to respond in some way when powerful blocs in American politics combine to resist him.

In the 24 hours after Trump’s comments in Helsinki, Democrats on Capitol Hill were of course furious about them. But so were some Republicans, including those who typically criticize Trump and even a few Trump allies. Dan Coats, the director of national intelligence, issued a statement affirming his confidence in the intelligence community’s findings that Russia had interfered in the 2016 election; issuing the statement was an aggressive step, since Coats is a Trump political appointee. And the media was unusually unrestrained in attacking Trump, a tenor perhaps best illustrated by CNN’s Anderson Cooper declaring on air that Trump’s behavior was “disgraceful,” and Fox News’ Abby Huntsman writing on Twitter that “No negotiation is worth throwing your own people and country under the bus.”

In short, Trump’s Russia comments had managed to greatly annoy Democrats, many Republicans, the press, and the leader of one of the most important bureaucracies in the U.S. government (the intelligence community) in one swoop. As a result, the president’s Helsinki comments were likely going to stay in the news and continue to be criticized, so he basically withdrew them (despite looking annoyed at having to do so). This is not the first time Trump conceded after facing this kind of broad opposition.

“Broad” is the key word there. Last year, we came up with a “Trump opposition meter,” identifying six powerful blocs who could limit or check Trump:

The federal bureaucracy. The courts. Democrats in Congress. Republicans in Congress. The public. The press.

The idea here is simple and pretty intuitive: The more of these groups that line up against Trump on a particular issue, the more trouble he’s in. Admittedly, that’s obvious on some level — of course a president is in more trouble if his own party is opposing one of his initiatives. But Trump’s actions generate so much outrage (much of it quite justified, in my mind) that we wanted a tool to separate 24-hour dust-ups from more serious controversies, and to help us judge when outrage and opposition might force the president to back down.

Last year, for example, all six of these blocs opposed Trump’s initial executive order establishing what’s referred to as the “travel ban” or “Muslim ban,” and that forced the administration to draw up a different version of the policy. Five blocs (the courts were not involved) disapproved of Trump’s decision to dismiss then-FBI Director James Comey, which led to a strong pushback from the bureaucracy in the form of the appointment of special counsel Robert Mueller. Opposition to Trump’s comments in the wake of the white nationalist rally in Charlottesville, Virginia, similarly crossed partisan lines in Congress and drew rebukes from the press and the public, so it reached Level 4.

In 2018, I would argue that the president’s remarks that people from “shithole countries” were trying to enter the U.S. was a Level 4 controversy (disapproval from the public, the press and representatives from both parties), and that the administration’s now-abandoned policy that was resulting in children being separated from their parents at the border was a Level 6, with federal judges and bureaucrats also signaling that they viewed the policy as wrongheaded.

Trump has most likely never come across our opposition scale — an outrage in and of itself! — but he probably knew he was in trouble after his comments in Helsinki once Republicans in Congress started to make some noise, joining the press, the bureaucracy and Democrats. (A CBS News poll released on Thursday found the president was on the wrong side of public opinion, too: 55 percent of Americans disapproved of Trump’s handling of the summit with Putin, compared to just 32 percent who approved.) He backed down from the family-separation less than a month ago, and the same opposition pattern was developing then.

It’s worth thinking about opposition to Trump among these groups as we look to three other major events that will (or could) happen in 2018. Can Democrats somehow shift the nomination of Brett Kavanaugh to the Supreme Court from a typical partisan fight — in which the public and the press are not taking strong anti-Trump positions — to something that mobilizes those blocs against the White House? Can Senate Republicans, the leading opponents of Trump’s tariffs policy, get the public and press more engaged on the issue and draw more Democrats into opposing the policy too? Are all the reports that Trump would consider removing Deputy Attorney General Rod Rosenstein or Mueller really just hype, since Trump knows that such a move is likely to draw at least Level 5 opposition almost immediately?

If you think the answers to the questions above are “probably not,” “no” and “probably yes,” you are getting the idea here. At least for now, there are some checks and balances on President Trump. I’m guessing James Madison intended that the most important check on a sitting president would be the person sitting in Paul Ryan’s chair, not Anderson Cooper’s. But this is American politics in 2018.