See more of the story

British police investigating the Manchester terror attack say they have stopped sharing information with the U.S. after a series of leaks that have so angered the British government that Prime Minister Therese May wanted to discuss them with President Trump during a North Atlantic Treaty Organization meeting in Brussels. What can Trump tell her, though? The leaks drive him nuts, too.

Since the start of this century, U.S. intelligence services and their clients have acted as if they wanted the world to know they couldn't guarantee the confidentiality of any information that falls into their hands. At this point, the culture of leaks isn't just a menace to intelligence-sharing allies; it's a threat to the intelligence community's credibility.

In 2003, President Bush reportedly authorized an aide to leak highly classified intelligence on Iraq to the New York Times to support his decision to go to war. It was an early indication that leaks would be used for political purposes and U.S. political leaders would deem it par for the course.

Then, in 2010, WikiLeaks began releasing U.S. intelligence data, including a report on how to stop the release of secret documents on WikiLeaks. That didn't stop Julian Assange's website from releasing secret data provided by Bradley (now Chelsea) Manning and, in 2013, by National Security Agency contractor Edward Snowden — two major troves of secret material.

In 2010, China began wrapping up the Central Intelligence Agency's asset network there. The agents disappeared or died one after another for the next several years. The CIA never quite figured out how the Chinese found out: It could have been a mole, or they could have hacked a communication channel. Five years later, Chinese hackers stole data about millions of U.S. government employees.

In 2012, CIA chief David Petraeus resigned after it came out that he'd leaked classified information to his lover and biographer, Paula Broadwell.

In 2016, the U.S. intelligence services accused the Russian government of hacking the presidential election campaign, in particular the Democratic Party's. After Trump won the election, leaks intensified to a frenzy, with unnamed former and current intelligence officials talking daily to the press about the Trump campaign's contacts with Russians. Overheard phone conversations with the Russian ambassador proved to be the downfall of National Security Adviser Michael Flynn. At the same time, NSA hacking tools were published online by a hacking group (leading to a recent WannaCry ransomware attack), and WikiLeaks revealed a less advanced but still effective CIA hacking arsenal.

The leakorama has grown bizarre lately. Sources leaked the allegation that Trump leaked sensitive intelligence data related to Islamic State to Russian Foreign Minister Sergei Lavrov, without revealing what exactly Trump said. The next day, someone leaked that the information leaked by Trump had come from Israel. Trump, on a trip to Israel, told reporters he'd never "mentioned the word Israel" to the Russians, denying something no one ever accused him of doing.

Trump has railed against the leaks privately (that has leaked out, of course) and on Twitter but has been unable to stop it. All he can do is join the ranks of leakers and do what Bush did, firing his own salvos in the anonymous war.

If this history has taught the U.S. intelligence community anything, it's that leaking classified information isn't particularly dangerous and that those who do it largely enjoy impunity. Manning spent seven years in prison (though she'd been sentenced to 35), but Snowden, Assange, Petraeus, the people who stole the hacking tools and the army of recent leakers, many of whom probably still work for U.S. intelligence agencies, have escaped any kind of meaningful punishment.

If no one gets punished for leaking, why not give classified information to the media just for fun? The Manchester leaks — the name of the terrorist and gory pictures from the scene — seem to fall into that category. The U.S. intelligence officials who provided that information to reporters had nothing to gain by doing it. They were just bragging that they knew stuff.

This, of course, isn't how agencies normally operate. After the Cambridge spy ring rendered the U.K.'s MI5 and MI6 transparent to Soviet intelligence for a while, the two services engaged in a massive coverup to avoid embarrassment. But the U.S. intelligence community doesn't mind serving as the world's biggest provider of sensational story ideas to the media. It doesn't act embarrassed, though the leaks mean it's been thrashed by rivals such as China and Russia, and it hasn't gone on lockdown to look for people within its ranks who appear to believe in the unlimited freedom of information, as long as it's anonymous.

Allies of the U.S. won't always be as open about withholding information as the British police have been. They will withhold it quietly, and they won't leak those decisions to the press.

The media has lapped up the leaks; reporters and their readers in the U.S. are used to trusting the intelligence agencies. But in the current unusual situation, reporters are the last line of defense. What if we're spreading lies, and what if we're putting people in danger by publishing what these anonymous sources tell us?