A FEW days into 2018, President Donald Trump pondered a recorded fall in the number of people apprehended on the border with Mexico and liked what he saw. Attempted border crossings are “way, way down” because migrants know they will fail, he told a bipartisan delegation from Congress. As if torn between claiming credit for intimidating toughness and promoting his signature promise to fortify the border with Mexico, he mused that migrants were being stopped by land, air and sea: “But we do need the wall, and we need more border security anyway.”

That was then. Less than three months later Mr Trump sees a very different border. On the defensive after some bad headlines, a jump in border crossings and agitated by Fox News TV reports of a “caravan” of Central American asylum-seekers and activists making its way through Mexico towards America, the president fired off several dawn choruses of tweets, denouncing “our “Weak Laws” Border”. In Twitter messages that in some cases cited ideas just voiced on Fox News, Mr Trump threatened to tear up the North American Free-Trade Agreement (NAFTA) if Mexico did not stop the migrant caravan, and to cut foreign aid to Honduras. He accused the migrants of seeking to “take advantage of DACA”, an Obama-era scheme to shield from deportation migrants who came to America illegally as minors. “Congress MUST ACT NOW!” he declared, and made a by-now-familiar demand for Republicans to eliminate the rule that most new laws can pass the Senate only with a 60-vote supermajority.

On April 3rd Mr Trump startled aides by calling for troops at the frontier. “We have horrible, horrible and very unsafe laws in the United States,” Mr Trump said. “We are preparing for the military to secure our border between Mexico and the United States.” The next day he signed a proclamation to deploy the National Guard.

As so often, there was much for fact-checkers to quibble over. Central Americans crossing Mexico cannot apply for DACA protections, which cover only migrants who arrived in America before 2012. The Republicans who control the Senate have no intention of scrapping the 60-vote threshold for legislation, fearing a loss of influence the next time Democrats hold the majority. Previous administrations have sent National Guard troops to the border as extra eyes and ears for border guards, but there are legal constraints on using soldiers for law-enforcement. In any case Central American asylum-seekers rarely hide from border agents, as their aim is to lodge a legal claim to stay.

But to fact-check Mr Trump’s tweets and crowd-pleasing impromptu utterances is of less use than monitoring his actions. Soon after taking office, he moved to “take the shackles off” America’s immigration police, particularly members of Immigration and Customs Enforcement (ICE). He signed an executive order deeming many undocumented immigrants “a significant threat to national security and public safety”, and vowing to enforce America’s immigration laws “against all removable aliens”. During his first nine months in office, arrests for immigration violations were 42% higher than they were during the same period in Barack Obama’s last year. Non-border deportations rose 25% in fiscal 2017. Deportations of illegal immigrants who have committed no other crime, and who were not a priority in the Obama era, nearly tripled. Refugee admissions have plummeted. This fiscal year 16% of them are Muslim, compared with 42% a year ago.

In recent years local police in many places with large numbers of undocumented immigrants—including Chicago, New York, Boston, Philadelphia and California, between them home to around one-third of the undocumented population—have grown less willing to co-operate with federal immigration authorities. Mr Trump has pressed localities to co-operate with federal authorities, even threatening to withhold government money until a judge ruled that unconstitutional.

ICE agents have increased their presence at courthouses. ICE said they will use courthouse arrests only for “specific, targeted aliens” with criminal records, gang affiliations or removal orders, or who pose national security threats. Some see that promise as more honoured in the breach than the observance. Jan Schakowsky, a congresswoman from suburban Chicago, contends that one of her undocumented constituents who fitted none of those categories was seized after a minor traffic violation, and held in a detention centre in another state for three days. Activists also complain about a rising number of “collateral arrests”— in which ICE arrests people who were not the original targets of a warrant, but were merely swept up in a raid.

This week’s presidential fury obscured substantive policy moves. The Department of Justice is to set quotas for clearing cases for immigration judges to hit. White House officials are drafting a package which would, among other things, make it easier to deport children who arrive alone at the border. Watch what Team Trump does, not what it tweets.