Trump waited only until the second paragraph of a stark convention speech in Philadelphia last year before hitting on the theme. He went on to describe a nation threatened by "attacks on our police, and the terrorism in our cities" and promising that as soon as he became President, "safety will be restored."
Now, flexing his presidential power, Trump is acting to implement that promise, even if his perception of a nation under siege to crime and violence is one not recognized by his critics or necessarily backed up by facts.
On Monday, Attorney General Jeff Sessions unveiled Trump's plan to reverse Obama administration curbs that prevented local law enforcement agencies from receiving surplus military gear, including including armored vehicles, grenade launchers, high-caliber weapons and camouflage uniforms.
The previous White House introduced the measures following violent clashes in Ferguson, Missouri, in the belief that police forces touting military-style gear came across as an occupying force in a way that heightened community tensions.
But on Monday, Sessions raised the specter of a war against police on America's streets as he addressed the Fraternal Order of Police.
"(W)e are fighting a multi-front battle: an increase in violent crime, a rise in vicious gangs, an opioid epidemic, threats from terrorism, combined with a culture in which family and discipline seem to be eroding further and a disturbing disrespect for the rule of law," Sessions said.
The attorney general also suggested that those who use individual violations of rights by officers to tarnish police services as a whole are effectively inciting attacks against them.
"Their divisive rhetoric treats police officers like the problem, instead of the crucial allies that you all are. So it can come as no surprise when we see rising levels of violence against law enforcement," Sessions said.
The administration's new plan, which could lead to the further "militarization" of police, was announced three days after Trump pardoned former Arizona Sheriff Joe Arpaio
-- a vehement supporter and lightning rod for claims of police brutality and racial discrimination.
While the pardon raised constitutional and political questions
, it was also clearly a show of support for ruthless law enforcement, since Arpaio was convicted of contempt in a case that involved racial profiling against Latinos.
Trump made little attempt to disguise his motives. Previewing his move last week in Arizona, he asked supporters whether "Sheriff Joe was convicted for doing his job?"
A White House statement confirming the pardon meanwhile made little attempt to lay a legal foundation for a ruling that opponents said was the latest sign of the way Trump views the implementation of justice largely through a political lens and in the context of how it affects himself or his base of supporters.
And on Monday, he was unapologetic about his decision -- though again did not offer a legal justification.
"He is very strong on borders, very strong on illegal immigration. He is loved in Arizona. I thought he was treated unbelievably unfairly."
A vision of "tough" policing and was at the center of Trump's campaign. It's also closely linked to the issue of immigration enforcement and how to handle undocumented immigrants, animating concerns for Trump's most loyal voters that helped power him to the White House last year.
And although Trump has expressed extreme frustration over Sessions' decision to recuse himself from oversight of the Russia investigation, an uncompromising stance on law enforcement unifies both men.
In May, for instance, Sessions issued a new directive to prosecutors to pursue the stiffest charge available in every criminal case that likely will result in more prosecutions of non-violent drug offenders and tougher sentences, rolling back measures introduced by the Obama administration designed to alleviate the societal costs of mass incarceration that fall disproportionally on minority communities.
Trump's stressing of a nation besieged by crime and depiction of those suspicious of law enforcement as merely too politically correct appears to be in line with his long-term political beliefs. But his decision to hit these themes hard now appears to be no coincidence. It comes at a moment when his presidency is in deep political peril, as he feuds with Republicans, deals with the worst approval ratings of any modern president at an equivalent moment and is hugging his base voters close. By promoting his tough guy persona on policing and societal issues, he may risk further dividing the country.
And some critics believe that Trump is bent on advancing the reach of the government in subsidizing military equipment for police.
"The militarization of our law enforcement is due to an unprecedented expansion of government power in this realm," said Republican Sen. Rand Paul on Twitter on Monday.
But Trump is also on solid political ground with a tactic that helps him speak directly to his own most faithful supporters and the Republican voting block as a whole.
Trump, under fire for his reaction to the violence in Charlottesville, Virginia, and what even many Republicans saw as his unacceptable decision to draw equivalencies between white supremacists and counter protesters is also hitting hard on other themes that often take on a racial dimension.
Last week, in the explosive rally in Arizona, Trump implied that American history, "culture" and patriotism was under threat, and criticized the drive to remove "beautiful statues" designed to commemorate the Confederacy.
Such rhetoric appears designed to communicate a tough image to Trump's political base, and to recreate the contempt for what his supporters see as rampant liberal political correctness -- that echoes his law and order rhetoric.
Civil rights concerns
Trump has repeatedly used the law and order theme to project strength.
He repeatedly warned of out-of-control and rising crime during his 2016 campaign, even if crime showed that over the last quarter century violent crime on the whole had fallen. The FBI however did report a 3.1% rise in violent crime in 2015.
In July, the President traveled to Long Island, and vowed to wipe out the MS-13 street gang, and appealed to police not to worry about getting too tough with suspects that he referred to as "animals."
"When you see these towns, and when you see these thugs being thrown in to the back of a paddy wagon -- you just see them thrown in, rough. I said please don't be too nice," Trump said.
The President's rhetoric on crime has sparked deep concern among civil rights groups, who worry that he is deliberately playing on the racial fault lines revealed in the criminal justice system for political gain.
The Lawyers' Committee for Civil Rights Under Law said Monday that the move to relax curbs on the militarization of the police will carve fresh divides between law enforcement officers and African-American and Latino communities.
"Once again, this administration is making clear its intent to revive ill-conceived policies that perpetuate racial disparities in the criminal justice system, hurt families and communities, and exacerbate the mass incarceration crisis across our country," Kristen Clarke, the group's president and executive director, said Monday.
There is clear evidence that while Trump's tough stand is politically divisive, it plays well with his base, and cements his role as an antagonist of what supporters see as a liberal approach to law and order that is steeped in political correctness.
In election exit polls last year
, for instance, 73% of Trump voters said that the criminal justice system treats everyone fairly. But 72% of those who sided with Democrat Hillary Clinton said that the system treats African-Americans unfairly.
And in a Quinnipiac University poll
this month, 73% of Republicans said there was too much political correctness in American life, compared to only 21% who believed there was too much racial prejudice.
And Trump may also be plowing fertile ground on law and order even when he addresses voters who don't always agree with him, underlining the potency of using law and order as a political tool.
The Pew Research Center
noted in a February report that public perception often does not measure up with data showing the crime rate falling.