At the very moment the Republican National Convention opened on Monday, before the midday chaos of a “rules rebellion” by anti-Trump delegates or the plagiarism controversy around Melania Trump’s evening speech, party chair Reince Priebus took the stage to honor Americans he called “genuine heroes.”

“I’d like to take a moment to recognize the fallen police officers in Baton Rouge, Dallas and elsewhere,” he said, “the men and women who protect our safety and well-being, who put their lives on the line every day.”

It was fitting, both as a tasteful tribute to officers lost and a preview of things to come.

For all the understandable media focus on “Melaniagate,” an inescapable message of Monday and even Tuesday was that America is under siege — under siege from foreign threats like “Islamic extremist terrorism,” under siege from undocumented immigrants and under siege from threatening protesters against the police.

Like Nixon before him, Trump has explicitly called himself “the law and order candidate,” and the first two days of his convention were filled with pitches on that theme.

Iowa Sen. Joni Ernst said ISIS is “present in all 50 states.” Speakers talked about the death of loved ones at the hands of undocumented immigrants. And there were several unmistakable knocks on Black Lives Matter.

“Blue lives matter in America,” said Milwaukee County Sheriff David Clarke, who is black. “We simply cannot be great if we don’t feel safe in our homes, on our streets and in our schools.”

Clarke was followed by another black speaker, Colorado Senate candidate Darryl Glenn, whose rebuke of the racial justice protestors was even less subtle, and slightly more bizarre.

“Somebody with a nice tan needs to say this,” he said. “All lives matter.”

Still, the height of the Monday’s “law and order” rhetoric may have come from former New York City Mayor Rudy Giuliani, who presided over a dramatic lowering of violent crime rates in the 1990s.

“The vast majority of Americans today do not feel safe,” he said. “They fear for their children. They fear for themselves. They fear for their police officers who are being targeted. … What I did for New York, Donald Trump will do for America.”

The mayor didn’t mention that he was criticized for his tough “Broken Windows” approach to policing as well as “stop and frisk” tactics disproportionately affecting people of color. Nor did he — or any of the other speakers — note that, in general, crime has been falling in the United States for decades.

What they’re hoping to capitalize on — or, more charitably, respond to — is that violent crime does appear to be up for 2015 and 2016, according to the FBI. Recent shootings in the headlines have contributed to a sense of unease.

New Jersey Gov. Chris Christie also took up the “lawlessness” theme Tuesday, when the former U.S. Attorney prosecuted the case against Hillary Clinton in his speech. He even referenced a fallen New Jersey state trooper, saying Clinton prevented his killer from facing justice by allowing her to remain in Cuba.

Critics charged that Christie’s speech actually undermined the “law and order” theme, as the crowd chanted “Lock her up!” in reference to Clinton — Republican strategist Steve Schmidt said on MSNBC that it had the feel of a banana republic.

Yet there’s no question this theme isn’t worn out. Appearing via video Tuesday night, Trump said there would be much more talk on “law and order” when he formally addresses the convention Thursday.

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