In 1991, I took a business trip to New York City soon after the birth of my son Andrew. Though my family had visited Manhattan through the most dreadful days of the 1970s and 1980s, the grim hopelessness that suffocated the “Ungovernable City” reached its nadir in the early 1990s. A travel magazine from that period listed New York alongside war-torn Sarajevo, Bosnia , in a ranking of the worst cities in the world to visit. Nothing I saw during that three-day trip made me question that conclusion.

My old station wagon was broken into on the trip’s first two nights; vandals shattered all of its windows for good measure on their second pass. Walking through Penn Station late at night was like touring the set of a dystopian horror movie. And a nighttime stroll through Central Park, these days considered romantic, would have then been evidence of a death wish. Murders in New York reached an all-time high in 1990 , while robberies and car thefts continued to explode upward. Natives of the Big Apple that I talked to during that period fondly recalled a bygone era when they could roam the city without fear. No one believed those days would return.

Four years later, after being elected to Congress, I reluctantly returned to New York for a House Armed Services Committee meeting aboard the USS Intrepid. Within minutes of leaving my Midtown hotel, I started peppering my hosts with questions.

“Where is the graffiti?” “When did Times Square stop smelling like a sewer?” “What happened to all the garbage on the street?”

Mayor Rudolph W. Giuliani and his police commissioner, William Bratton, are what happened. Their groundbreaking policies led to the reversal of a crime epidemic that was strangling the soul of New York City.

Giuliani’s record on crime ranks among the greatest public-policy achievements of the 20th century. Under him, violent crime in the city dropped 56 percent, murders and robberies plunged by two-thirds, and property crimes fell 65 percent. Critics still cite an improving economy, the crack epidemic’s end and the policies of Giuliani’s predecessor as mitigating factors. But let’s give credit where credit is due.

Beyond those historic achievements, it would be Giuliani’s inspired leadership in the days after the terrorist attacks of Sept. 11, 2001, earned him the title “America’s Mayor.” Before President George W. Bush found his voice on top of a pile of rubble at Ground Zero, it was Giuliani who projected compassion, determination and defiance during those trying times. Giuliani struck nothing less than a Churchillian pose when that inspired leadership was so necessary for New York and the rest of the world.

Why do I choose today to excavate Giuliani’s record as mayor? Because this week, that same man became the latest public figure to assume the role of henchman for President Trump, stooping so low as to slander the very law-enforcement institutions that made New York’s remarkable renaissance possible.

During his Wednesday night appearance on Fox News’s “Hannity,” Giuliani was so desperate to protect the president from the fallout over his porn-star payoff that he compared FBI agents and prosecutors in the Southern District of New York to Nazi stormtroopers. And what grave offense did these pillars of American law enforcement commit to earn such a damning rebuke?

They did exactly what then-U.S. Attorney Giuliani did during his own time as the Southern District’s top prosecutor. In pursuing their investigation into Trump fixer Michael Cohen, the U.S. Attorney’s office went to a federal court, argued for a warrant based on probable cause, conducted a constitutionally approved search and gathered evidence to either prove or disprove that the subject had committed a crime. As Giuliani himself said of the search on Cohen’s apartment, home and office: “Is it extraordinary? No. This is the way prosecutors get information — sometimes to convict and prosecute, sometimes to exculpate.”

But that was Giuliani way back on April 9 — before he joined Trump’s team of misfit lawyers.

Why America’s Mayor would now allow himself to become Trump’s chump is beyond me. With many West Wing insiders openly questioning whether the 45th president will even finish his term, such shortsightedness makes no sense, even when viewed in the most cynical of lights.

Giuliani has said that in September 2001, during New York’s darkest hour, he drew strength from Winston Churchill’s example. That is curious considering the great British leader stood alone for years while warning the world of Hitler’s dangers. That lonely stand isolated him from kings, prime ministers and his own political party. And yet poor Rudy couldn’t even stay true to his former colleagues for a month once Trump came calling.

We can all thank God that Churchill, and not Giuliani, was on guard when Adolf Hitler’s actual stormtroopers sought to destroy England and lay waste to the rest of Western civilization. Because unlike Rudy Giuliani, Winston Churchill never blinked.

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