We have seen all of this before, employed by the K.G.B. and the East German Stasi: psychological warfare, rumor-mongering, schemes to bribe politicians and then expose them as criminals. They used it both internally, against dissidents, and externally, against Western enemies. Mr. Putin and his former K.G.B. colleagues should know that, this time, we have a better sense of their dirty tricks, and how they have updated Zersetzung for the internet.

The government has its role to play, but so do journalists and civil-society groups. We journalists will put pressure on companies like Facebook and Twitter to be vigilant against fake news; we will expose the patterns of Russian agitprop where we see them.

But it is just as important to be clear about the ideology driving these attacks. In September, my newspaper, Die Zeit, joined with the broadcaster ZDF to reveal details of Moscow’s highly sophisticated disinformation campaign. We had gained access to roughly 10,000 emails that showed how ideologues close to the Putin administration advised the pro-Russian rebel government in Eastern Ukraine.

Among the emails was a document that set “thematic guidelines” which rebel-allied media outlets had to follow — if necessary by distorting facts and faking news. “Today’s Russia is no longer the Russia of the 1990s, but is working unwaveringly to re-establish the strength of the Soviet Union. Today’s Russia is on an equal footing with the West,” it read. “A global diplomatic war is underway. But the West is also suffering in this war, and it is still unclear who will prevail.”

No doubt similar marching orders have been given to the armies of hackers who were sent to attack the Democrats, and who are now plotting attacks on Germany.

It is quite clear who will lose. Mr. Putin and his reckless fakers should be aware that the only thing they will harvest from this mendacity is another lost generation of Russians who could serve their country better by being given the opportunity for honest and constructive intellectual challenges. A government that maligns the outside world to make feel Russia great again is doomed to fail — as it failed before.