There is no connection, of course, between the prosecution of notorious gangster James “Whitey” Bulger and the recent spate of scandals and revelations roiling the Obama administration. Or is there?

Law enforcement and criminal justice are essential functions of government. No civilized society could survive for long if it lacked tools to combat lawlessness or make dangerous villains answer for their crimes. And Bulger was certainly dangerous – “one of the most vicious, violent criminals ever to walk the streets of Boston,” as Assistant US Attorney Fred Wyshak called him in summing up for the prosecution last week.

But Bulger wasn’t the only one on trial in Boston’s federal courthouse. So was the government trying him. Bulger and his henchmen may have been the degenerates who physically committed the gruesome murders and other crimes that jurors learned about during 35 days of sometimes stomach-churning testimony. But it was other degenerates, in the FBI and the Justice Department, who for so long enabled Bulger’s bloody mayhem. They enlisted Bulger as an informant, protected him from police investigations, and warned him to flee when an indictment was imminent. “If the FBI had not made Whitey its favorite mobster, broken the rules, and rigged the game to his benefit,” reporter David Boeri has concluded, “Bulger would never have reached as high as he did.”

The corruption of the federal government was a key element in Bulger’s trial, as it was in so much of his sadistic career. Officials charged with defending the public from gangsters like Bulger used their considerable influence to defend the gangster instead.

It would be comforting to believe that this was a one-off, that law enforcement agencies never abuse their authority, that the immense powers of the federal government are always deployed with scrupulous integrity. But no one believes that.

As Bulger’s racketeering prosecution was playing out in Boston, other stories of federal overreach, secrecy, and obstruction were making headlines: The scandal at the Internal Revenue Service, which for more than two years had targeted conservative grassroots groups for intimidation and harassment. The Justice Department’s unprecedented designation of national-security reporter James Rosen as a “co-conspirator” in order to trawl through his personal email, and its surreptitious seizure of telephone records from up to 20 Associated Press reporters and editors. The disclosure that the National Security Agency’s collection of domestic communications data is far more intrusive than was previously known, with the NSA reportedly collecting billions of pieces of intelligence from US internet giants such as Google, Facebook, and Skype.

President Obama insists that none of this should undermine confidence in the federal government. “You’ve grown up hearing voices that incessantly warn of government as nothing more than some separate, sinister entity,” he told Ohio State’s graduating class in May. “You should reject these voices.”

At a press conference in June, he likewise assured Americans that they needn’t worry about the NSA’s vast data-mining operation being abused. “We’ve got congressional oversight and judicial oversight,” he said. “And if people can’t trust not only the executive branch, but also don’t trust Congress and don’t trust federal judges to make sure that we’re abiding by the Constitution and due process and the rule of law, then we’re going to have some problems here.”

According to Gallup, nearly half of Americans believe that the federal government “poses an immediate threat to the rights and freedoms of ordinary citizens.” A Rasmussen Poll asks whether the NSA’s metadata is likely to be used by the government to persecute political opponents; 57 percent say yes. Maybe we do have some problems here.

Or maybe Americans are remembering that government is always dangerous, regardless of the party in power. “If men were angels, no government would be necessary,” James Madison famously wrote. Alas, men are never angels, not even those entrusted with political authority. “In framing a government which is to be administered by men over men, the great difficulty lies in this: you must first enable the government to control the governed; and in the next place oblige it to control itself.”

The Bulger trial, the IRS scandal, our gigantic surveillance state – they are only the latest reminders that even the best government in the world depends on human beings, with all their human vices and appetites. Politicians, regulators, and law enforcement agents are as capable of villainy as anyone else. Government is dangerous, and should always be handled with care.

(Jeff Jacoby is a columnist for The Boston Globe. His website is www.JeffJacoby.com).