In the realm of military tactics, a raid can serve many purposes. It can keep the enemy off balance. It can probe for weakness. In the words of the ancient Chinese military strategist Sun Tzu, “You can be sure of succeeding in your attacks if you only attack places which are undefended.”

Shifting now to the realm of political tactics, we see that Donald Trump is a raider. That is, the political warrior in the White House is attacking the Democrats in places where they didn’t expect to be attacked.

Such as in Baltimore. In July, Trump launched a volley of tweets aimed at the district of Congressman Elijah Cummings. Trump bullseyed the Maryland Democrat for his supposed culpability in the misgovernment of the city of Baltimore. As the president put it, Cummings’ district is “considered the Worst in the USA…the worst run and most dangerous anywhere in the United States.”

Continuing to raid in that vein, Trump added that Baltimore is “corrupt,” a “disgusting, rat and rodent infested mess…very dangerous & filthy,” where residents are “living in hell.”

So what’s going on here? Some say that Trump’s blasts at Cummings were payback for Cummings’ attack on the administration’s border security policies—and perhaps, too, Trump was pushing back against subpoenas issued by the House Oversight Committee, which Cummings chairs. Others say that Trump was simply inspired by lurid reports from Fox News.

All these explanations could be true, yet still, Trump seems to have a larger strategy, one that points toward the 2020 election.

You see, even though he’s been called a “racist” for his attacks on mostly black Baltimore, he has undeniably thrown Cummings, and his city, on the defensive. After all, even the liberal-leaning news reports that defend Cummings and attack Trump typically mention that the murder rate in “Charm City” is soaring; indeed, Cummings’ district has the third-highest rate of gun violence in the nation. (Trump pounced again when reports said that Cummings had suffered a home invasion.)

In other words, Trump’s raiding strategy has enjoyed some success; once again, he has diverted attention from his own vulnerabilities. Of course, in terms of the 2020 election, Baltimore itself is not in play; in 2016, Trump won a mere 10.5 percent of the vote there. And the state of Maryland, boasting 10 electoral votes, also seems out of reach; three years ago, Trump won less than 34 percent of the vote.

Yet in the minds of his supporters, Trump’s raid has revealed the weaknesses of his enemies—look how terrible those Democratic cities are!

Yes, of course, Democrats, including Cummings, will continue to attack Trump; they might even seek to impeach him. Yet now we know that Trump and his allies will dish it right back in 2020: the Democrats want to do to the United States what they have done to Baltimore.

Indeed, as a kind of parting shot on July 29, the tweeter-in-chief quoted one of his black supporters: “A lot of Democratic run cities all over America look like this, it’s not just Baltimore, unfortunately.” Thus can we see that Trump will likely raise the issue of the Democrats’ urban malfeasance across the nation.

In fact, even as he was going after Cummings, Trump also went after an urban target on the other coast: “Speaking of failing badly, has anyone seen what is happening to Nancy Pelosi’s district in San Francisco. It is not even recognizable lately. Something must be done before it is too late.”

And Team Trump has more up its sleeve than just dyspeptic tweets. On September 10, The Washington Post blared this headline: “Trump pushing for major crackdown on homeless camps in California, with aides discussing moving residents to government-backed facilities.”

Needless to say, the article included plenty of spluttering outrage from Democrats, as well as not-so-subtle chiding from reporters. The Post pointed out, for example, that the Trump administration has sought to cut the budget of the Department of Housing and Urban Development by 20 percent. (Of course, some will say that there’s hardly a strong relationship between budgetary inputs and real-world outcomes.)

Yet once again, even as the left railed against Trump, the reality of conditions in leftist precincts was impossible to hide. That same Post article featured ugly pictures from San Francisco and equally ugly statistics concerning homelessness in California. To any fair-minded observer, it’s obvious that something went wrong with municipal order long before Trump entered the White House. That’s why there are perhaps 10,000 homeless people in San Francisco and 50,000 to 60,000 in Los Angeles.

Two days later, on September 12, the Post bannered another story on the emerging Trump initiative, offering, of course, still more criticisms. Yet it also further journalistically excavated the homeless problem—and that’s a mission accomplished for the president.

In fact, that same Post story also included this intriguing quote from Democrat and Sacramento mayor Darrell Steinberg, chairman of the state’s Commission on Homelessness and Supportive Housing (emphasis added): “I am wary because every time this president does anything involving people who are vulnerable, they are the ones who get hurt. And yet, that being said, we have an obligation to better understand if there are federal resources out there to help address California’s homeless problem.”

In other words, Steinberg, at least, wants to talk to the Trumpians. And it’s entirely possible that some time soon, HUD Secretary Ben Carson will visit California, looking to scope out federal facilities that might be put to use to provide homes for the homeless. And who knows: perhaps Trump himself will come west to look things over—and stir things up.

In fact, just on September 17, on his way to fundraisers in California, Trump told reporters aboard Air Force One, “We can’t let Los Angeles, San Francisco and numerous other cities destroy themselves by allowing what’s happening,” and he added that he was considering setting up a new federal task force on homelessness.

As with Maryland, it’s impossible to imagine that Trump’s concern over California’s urban blight will win him the Golden State’s electoral votes. Yet even so, he’s still registering with those who are horrified by California’s homelessness. One such is Lydia DePillis, a veteran journalist now perched at Pro Publica. On September 13, she was moved to tweet, “Razing homeless camps is inhumane and this seems more motivated by politics than humanitarianism but also…a real sense of federal urgency around homelessness is refreshing? And converting available government buildings into low-income housing would be good?”

In other words, amidst the failures of the status quo, Trump is getting at least some credit for wanting to try something new.

To be sure, it’s entirely possible that nothing much, in terms of actually reducing homelessness, will come out of this initiative. That is, legal and political opposition—including, inevitably, street protests—could stymie the feds, just as local and state officials have been stymied.

Yet if Trump is turned back on addressing the problem, it’s a safe bet that he won’t turn the other cheek on addressing the politics. That is, he’ll come out swinging against the Democrats, accusing them of incompetence, waste—and worse. Why, Trump might even summon up the rhetoric of three-term New York City mayor Ed Koch, who back in the ’70s and ’80s based his campaigns on opposition to “poverty pimps” and “poverticians”—and Trump remembers Koch well. (Koch was a Democrat, but on urban issues, he was no liberal.)

Indeed, in attacking the cities, Trump is plucking a resonant chord in American political history. That is, the cities, in their, uh, yeastiness, have always been a fat target for reformers.

For instance, back in 1901, one of Koch’s mayoral predecessors, Seth Low, was elected as a Republican on a reform agenda, targeting the crooks of New York City’s Tammany Hall. That same year, McClure’s launched a series of articles on urban poverty and corruption across the nation; these pieces were later turned into a best-selling book, The Shame of the Cities.

We can add that this muckraking was much admired by the New York City-born Republican in the White House, Theodore Roosevelt. In his 1902 message to Congress, the 26th president took up the cause of urban reform. Focusing on the one city that the federal government controlled, the District of Columbia, TR inveighed against “the evils of slum dwellings,” pledging “hygienic and sanitary legislation.” In those days, D.C. couldn’t vote, yet across the nation, high-minded folks who could vote were reassured that their president was working hard to clean up the cities. In 1904, TR was re-elected in a landslide.

Now, more than a century later, another New York City-born Republican abides in the White House. Admittedly, it might seem absurd to compare Trump to TR, yet the fact remains that, then and now, some parts of urban America were and are a swamp, much in need of draining. And if TR isn’t available, why not Trump? His political raids might not solve the problems, but they can certainly highlight the problems.

Indeed, urban problems seem only to be proliferating. On September 7, the Washington Post took note of a D.C. charter school—an urban boarding school with a distinctly spotty record of attendance and safety—that spends an astonishing $72,000 per student per year. D.C., of course, is even more Democrat-dominated than Maryland or California.

So now, on top of the shame of crime and homelessness, Trump might add the shame of urban education. Sweeping all these shames into one broadside, he can ask: is this the sort of governance that Democrats will usher in nationwide if they win next year? Do the American people want the horrors of Baltimore, San Francisco, and D.C. to come to Anytown?

Come to think of it, in next year’s campaign season, other Republicans might wish to do some raiding of their own. Or, to put the matter less martially, they might start pushing for reform, asking hard questions about the shame of the cities.

It’s worked before.

James P. Pinkerton is an author and contributing editor at The American Conservative. He served as a White House policy aide to both Presidents Ronald Reagan and George H.W. Bush.