You may have missed this story, so I am repeating it as a public service:MOSCOW, Special to The New York Times, Oct. 1 — A previously unheard-of group called Hackers for a Free Russia released a treasure trove of financial records online today indicating that President Vladimir Putin owns some $30 billion in property, hotels and factories across Russia and Europe, all disguised by front organizations and accounting charades.

The documents, which appear to be authentic, include detailed financial records and emails between Mr. Putin’s Kremlin office and a number of his Russian cronies and Swiss banks. They constitute the largest hack ever of Mr. Putin. Russian censors are scrambling to shut down Twitter inside the country and keep the emails out of Russian-language media.

At a news conference in Washington, C.I.A. Director John Brennan was asked if U.S. intelligence services had any hand in the cyberleak of what is being called “The Putin Files.” With a slight grin, Mr. Brennan said: “The U.S. government would never intervene in Russian politics, just as President Putin would never intervene in an American election. That would be wrong.” As Mr. Brennan left the podium, though, he burst out laughing.

No, you didn’t miss this story. I made it up. But isn’t it time there was such a story? Isn’t it time we gave Putin a dose of his own medicine — not for juvenile playground reasons and not to instigate a conflict but precisely to prevent one — to back Putin off from what is increasingly rogue behavior violating basic civilized norms and increasingly vital U.S. interests.

Putin “is at war with us, but we are not at war with him — both the U.S. and Germany are desperately trying to cling to a decent relationship,” remarked Josef Joffe, editor of Die Zeit, a weekly German newspaper and a leading strategic thinker in Europe. No one should want to start a shooting war between great powers “in the shadow of nuclear weapons,” Joffe told me.

But we also cannot just keep turning the other cheek. Putin’s behavior in Syria and Ukraine has entered the realm of war crimes, and his cyberattacks on the American political system threaten to undermine the legitimacy of our next election.

Just read the papers. Last week a Dutch-led investigation adduced irrefutable video evidence that Putin’s government not only trucked in the missile system used to shoot down a Malaysia Airlines plane flying over Ukraine in 2014, killing all 298 civilians onboard, but also returned it to Russia the same night and then engaged in an elaborate cover-up.

On Sept. 19, what U.S. intelligence officials say was almost certainly a Russian Su-24 warplane bombed a U.N. convoy in Syria carrying relief supplies for civilians. The Red Cross said at least 20 people were killed. U.N. Secretary General Ban Ki-moon called the bombing “savage and apparently deliberate.”For a long time, Putin’s excesses were just a tragedy for the Russian people and for many people in Ukraine and Syria, so President Obama could plausibly argue that the right response was economic sanctions and troop buildups in Eastern Europe. But in the last nine months, something has changed.

Putin’s relentless efforts to crush both the democratic and Islamist opposition to President Bashar al-Assad in Syria; his rejection of any real power-sharing solution there; and his joining with Assad in mercilessly bombing civilians in Aleppo are not only horrific in and of themselves, but they also keep pushing more refugees into the European Union. This is fostering an anti-immigrant backlash in Europe that is spawning right-wing nationalist parties and fracturing the E.U.

Meanwhile, Russia’s hacking of America’s Democratic Party — and signs that Russian or other cyberwarriors have tried to break into American state voter registration systems — suggests that Putin or other cyberdisrupters are trying to undermine the legitimacy of our next national election.

Together, these actions pose a threat to the two pillars of global democracy and open markets — America and the E.U. — more than anything coming from ISIS or Al Qaeda.

“The Soviet Union was a revolutionary state that sought a wholesale change in the international order,” observed Robert Litwak, director of security studies at the Woodrow Wilson International Center for Scholars and author of “Deterring Nuclear Terrorism.” Putin is ostensibly not seeking a revolution of the international order, Litwak added, but Putin’s departure from standard great-power competition — encouraging a flood of refugees and attacking the legitimacy of our political system — “is leading to shifts in global politics that could have revolutionary consequences, even if Putin is not motivated by revolutionary ideology.”

Obama believed that a combination of pressure and engagement would moderate Putin’s behavior. That is the right approach, in theory, but it’s now clear that we have underestimated the pressure needed to produce effective engagement, and we’re going to have to step it up. This is not just about the politics of Syria and Ukraine anymore. It’s now also about America, Europe, basic civilized norms and the integrity of our democratic institutions.

<THOMAS L. FRIEDMAN>