To an impressive degree, Trump is defined by his harsh immigration policies. Photo: John Moore/Getty Images

It’s often said that immigration — or perhaps some narrower subtopic like a border wall — is Donald Trump’s “signature” issue. That could refer to the uninhibited zest with which he typically talks about the threats he associates with “open borders” and the violent criminals, terrorists, and assorted riffraff he claims are pouring over them to prey on Americans and the U.S. Treasury. Or it could allude to the central role this issue played — along with the closely associated “birther” mania — in his shocking transformation from a semi-comic entertainment figure to a serious candidate for the presidency in 2016.

But however you define Trump’s relationship to this latest phase of the American nativist tradition, it is increasingly clear that support for Trump means support for his immigration policies — and vice versa. This is made graphically evident by a new Axios–Survey Monkey survey that compares Trump approval ratings generally to approval of Trump on immigration policy in a variety of population subgroups — and shows remarkable congruity.

This begins at the most general level, with 44 percent of Americans approving of the job Trump is doing as president (29 percent strongly), and 43 percent approving (27 percent strongly) of his handling of immigration policy. An identical 55 percent disapprove (with an identical 44 percent doing so strongly) of Trump generally and Trump on immigration.

The pattern of Trump support being nearly identical to approval of his immigration policies continues through all sorts of demographic groups in the Axios–Survey Monkey poll. Among rural Americans, 57 percent approve of Trump’s job performance, and 58 percent approve of his immigration policy. Among seniors, it’s 50 percent and 50 percent. Among suburbanites, it’s 43 percent and 43 percent. Among white non-college graduates, it’s 59 percent and 59 percent. Among millennials it’s 33 percent and 31 percent.

If there’s some substratum of Democrats who don’t like Trump but are attracted to his immigration policies, it’s not very apparent in this survey: a booming 7 percent of Democrats and Democratic-leaning independent approve of the job Trump is doing generally, and an identical 7 percent like his immigration policies. And even though Trump conspicuously reversed the prevailing GOP support for comprehensive immigration reform prior to 2016, 88 percent of Republicans and GOP-leaning independents profess support for Trump’s immigration policies (63 percent approve of them strongly), just short of the 92 percent who give a thumbs-up to Trump’s job performance generally (67 percent of them strongly).

In case you think general attitudes on immigration policy don’t track positions on specific sub-issues, it’s worth noting that the Axios–Survey Monkey survey shows highly consistent overall and subgroup positions on Trump’s best-known individual policy, the construction of a border wall. Forty-five percent of all Americans support the border wall, just above their levels of support for Trump generally, and Trump’s immigration policy, with slightly higher intensity of support. The striking similarities track through just about all the demographic groups, with slight variations: 10 percent of Democrats (with leaners) support a border wall, which is probably attributable to the fact that 55 percent of seniors like the idea of sealing off the national lawn from unruly interlopers.

You can claim that this is all tautological, and that once you love (or hate) Trump you love (or hate) everything he does. But there have been surveys of support for Trump’s economic policies that are clearly out of sync with his overall support levels. And it’s not just that support for Trump and his immigration policies is similar or consistent: it’s eerily near-identical across just about every category a pollster can devise. If nothing else, the data are inconsistent with the commonly held assumption that a lot of people support Trump because the economy’s good or he’s given them a tax cut or he’s trying to ban abortion — but these same people don’t much care for his immigrant-bashing.

If Trump often acts as though agitating the air on immigration (as in his periodically renewed threats to shut down the government if he doesn’t get his border-wall money) is mother’s milk for his electoral “base,” it’s because there is abundant evidence that he’s right. Yes, the whole base-mobilization strategy for a midterm election can be perilous insofar as Trump could simply rev up the already high levels of enthusiasm among anti-Trump demographic groups, who clearly dislike his immigration policies as much as they dislike POTUS himself. But this is indeed Trump’s signature issue and it should not be surprising that he wants to talk about it as often as possible. He is the quintessential hammer to whom everything looks like a nail.