If Donald Trump’s triumph on Friday lacked anything, it was that Mexico had staved off a demand to change its asylum policies. The Trump administration had demanded that Mexico adopt the “safe third country” protocol, by which asylum seekers would have to apply in the first safe country in which they set foot. President Andrés Manuel López Obrador had insisted that he would never agree to it, and it appeared he successfully resisted it — while making a series of other concessions to avoid tariffs.

Today, however, Mexico conceded that the issue will be on the table if the commitments made on Friday don’t produce significant reductions in immigration flow:

Reuters reports on the same comments, although their coverage makes it sound more passive:

Mexican Foreign Minister Marcelo Ebrard said on Monday that measures agreed with the United States last week to stem the flow of U.S.-bound migrants entering Mexico from Central America will be evaluated after 45 days.

Speaking at a regular government news conference alongside President Andres Manuel Lopez Obrador, Ebrard said if Mexico managed to reduce the number of people entering the country, it would show steps taken by the Mexican government are working. …

There was no specific migration reduction target, Ebrard said, noting that when he began talks in Washington last week to defuse the tariff threat, the U.S. government wanted Mexico to accept a “safe third country” agreement over migration.

Mexico rejected this demand, which would have forced the Mexican government to accept many of the migrants detained trying to enter the United States by making them submit their asylum claims in Mexico rather than with U.S. authorities.

Ebrard noted that U.S. authorities wanted to cut the number of migrants to “zero” and said Washington would likely repeat its “safe third country” demand if Mexico was not able to bring down the number of people crossing illegally into the country.

However, the actual quote from Ebrard makes it more clear that Mexico knows that they will have to discuss this if they can’t show progress. That’s what they told Mike Pence when meeting with him on Friday, and how they got Trump to call off the tariffs — for now:

“In the meeting with the vice president of the United States, they were insistent on the safe third country issue. We told them — I think it was the most important achievement of the negotiations — ‘let’s set a time period to see if what Mexico is proposing will work, and if not, we’ll sit down and see what additional measures'” are needed, Ebrard told a press conference.

To put it plainly, Mexico pledged to either put up or shut up about their lingering objections to the “safe third country” protocol. Trump made that clear in his tweets this morning, as well as hinted at it on Friday by announcing that tariffs had been “indefinitely suspended” rather than canceled:

The joint declaration by both countries over the agreement made that plain as well. Both countries agreed to further review of the impact from the agreement and “further action” if the crisis didn’t ease as a result:

Both parties also agree that, in the event the measures adopted do not have the expected results, they will take further actions. Therefore, the United States and Mexico will continue their discussions on the terms of additional understandings to address irregular migrant flows and asylum issues, to be completed and announced within 90 days, if necessary.

In other words, Mexico has 90 days to prove that the “safe third country” protocol isn’t needed. If they don’t significantly slow down the flow of illegal immigration, they know that Trump will be back with a demand to implement the “safe third country” protocol — and that they’ll have little choice at that point but to adopt it.

That concession makes hash of media coverage today. Outlets have adopted the line from Trump’s critics that the agreement was a “sham” consisting of nothing more than the status quo ante. López Obrador and Ebrard clearly don’t think they just extended the status quo; they’re both telling the media that they now have to produce some significant reductions or get forced into adopting a North American standard on asylum that they have bitterly opposed until now. That’s not a win by any measure, and it’s arguably an embarrassing setback for López Obrador, who started off the fight by insisting that Mexico had nothing to offer.

The catalyst for that shift is clearly nothing else but the threat of tariffs. Trump reset the entire security balance by tying it to trade, and it worked. It might not be the right tool for every international issue, and it might not be wise in the long term to keep tying trade to other issues, but this tool was about the only one left in dealing with Mexico’s intransigence on securing its southern border.

It’s fine to reserve judgment until we see whether this has any appreciable effect on the border crisis, but pretending — as the media has been all weekend — that nothing’s changed is silly beyond belief.