President Trump makes two arguments in opposition to immigration, both debatable.

The first is economic, that immigrants in the country illegally (and even many here legally) undercut American workers. A report from the National Academies of Sciences, Engineering and Medicine released last year disputes that claim.

The second argument Trump makes — the argument he makes more frequently — is that immigration leads to and is a significant cause of crime in the U.S. There’s his claim that we need to build a wall on the Mexican border to cut down on drug smuggling and criminal illegal aliens, though most smuggling happens through existing checkpoints and immigrants are less likely to commit crimes than native-born Americans.

Trump also argues that immigration heightens the threat of terrorism in the United States. This is the motivation for his calls for a ban on Muslim immigration on the campaign trail, which evolved into his travel ban as president. Often when there’s an apparent terror attack overseas Trump rushes to link that attack to the need for greater protection in the U.S. (sometimes even before it’s acknowledged as a terror attack).

On Friday morning, Trump once again rushed to tie bad news from across the Atlantic to his domestic policy priorities, via Twitter.

We must keep America safe, Trump argues, because, quote, “United Kingdom crime rises 13% annually amid spread of Radical Islamic terror.” What’s being quoted there isn’t clear; Google doesn’t return any article that includes such a sentence and it apparently wasn’t on “Fox and Friends.” (Update: Media Matters tracked it down. It was on OAN.) The source of the quote is important because knowing where it came from would presumably allow us to understand the argument underlying the claim. Without that argument, we’re left with the statement itself.

Let’s at least evaluate that.

The 13 percent increase comes from a report released on Thursday by the Office for National Statistics in the United Kingdom. The Post called ONS and asked if the claim made by Trump was an accurate assessment of what they found.

“The simple answer,” a spokesman told us by phone, “is that our statistical release bulletin yesterday made no link between terrorism and violent crime.”

We asked what the less-simple answer was.

“That is the answer,” he replied. “There is a simple answer. There is no long answer.”

The ONS’ John Flatley provided an overview of the findings in the report itself.

“Today’s figures suggest that the police are dealing with a growing volume of crime,” he wrote. “While improvements made by police forces in recording crime are still a factor in the increase, we judge that there have been genuine increases in crime — particularly in some of the low incidence but more harmful categories.”

Those improvements in recording crime are one reason that the number of sex crimes has increased, up 19 percent year-over-year. In 2014, the report indicates, inspections of crime data revealed “significant under-recording” — suggesting that those prior data were too low.

There was a datapoint that terrorism affected directly. The number of attempted murders rose 59 percent year-over-year — a function of people being wounded in terror attacks in London and Manchester, which accounted for nearly 70 percent of that increase.

The number of homicides actually fell 2 percent, year over year — a fall which, weirdly, is due to a mass casualty incident in 1989. The U.K. counts a homicide in the year in which it was identified as a homicide, not the year in which the death occurred. A number of deaths related to a stampede at a soccer game in Hillsborough that occurred nearly 30 years ago were first counted in the 2016 tally, so the 2 percent drop year-over-year in the new data is a drop compared to the deaths in 2016 plus the Hillsborough count. If you exclude Hillsborough from the 2016 totals and the deaths in terror attacks in London and Manchester, the number of homicides increased 8 percent.

The biggest increases were in stalking and harassment and robbery. The increase in the number of crimes labeled “violence with injury” was up 10 percent — the increase in those labeled “violence without injury” was up 21 percent. This doesn’t seem like a crisis driven by international terrorism.

It’s also worth noting that top-line crime numbers in the U.K. and the U.S. aren’t apples-to-apples. Here, violent crime includes only four offenses: murder, forcible rape, robbery and aggravated assault. In the U.K., the definition of victim-based crimes is broader, also including stalking and harassment, certain robberies and thefts and criminal damage and arson. It’s this broader group of crimes that increased 13 percent, according to the ONS report.

Why Trump’s tweet, then? Perhaps he read the exact phrase he tweeted somewhere and thought the argument underpinning it was convincing.

Or, perhaps, he saw an opportunity to again try to raise the specter of terrorism as a threat to the U.S. and — days after yet another court blocked yet another one of his travel bans — wanted to suggest that the terror was leading to immediate, frightening effects in the U.K.

The gentleman we spoke with at the agency that actually did the counting didn’t seem to agree.

This article has been corrected to explain what happened at Hillsborough.