On March 12, 2014, long before anyone could imagine Donald Trump becoming President of the United States and concepts of “fake news” and “alternative facts” turning into global buzzwords, a group of journalists gathered outside a Ukrainian military base in Perevalnoe, outside Simferopol, the regional capital of Crimea. Standing next to several dozen screaming protestors, the journalists, many of them from Russia, watched how hundreds of soldiers armed with Kalashnikovs and light antitank missiles and wearing balaclavas and brand-new insignia-free uniforms, lined up along the perimeter of the long concrete fence surrounding the base.

The events unfolding in Crimea were so bizarre, so unprecedented, none of us journalists quite knew how to describe them. Later, Russian channels would call it “re-unification” and the rest of the world would label it annexation but at the time no one could be quite sure what Putin’s game in Crimea was. The Russian media, however, seemed to have been under strict orders. “Do these soldiers look like volunteers to you?” a chain-smoking Russian TV journalist in Perevalnoe asked me, crowning the rhetorical question with an elaborate profanity. As journalists find their way in our post-fact, post-truth world, they should learn from the mistakes the Western media made in Ukraine.

Minutes earlier I had overheard him on his phone with the editor in Moscow after his TV crew lost their live link to the studio. The editor told him the link had been cut because the reporter called Russian soldiers Russian soldiers and that he would either have to stick to “volunteer battalions” or leave Crimea. “I am ashamed,” said the journalist, who asked me not to name him. But from then on, following his editor’s and Vladimir Putin’s lead, he would only refer to the Russian troops in Crimea as “self-organized volunteer battalions.” A mortgage and three children, he explained to me, is what made him stick to the lie.

Western journalists covering Crimea and the subsequent war in Eastern Ukraine did not have to make difficult moral choices, but they too were pushed into an alternative reality constructed by the Kremlin, and involuntarily aided its narrative. Fast forward three years and today we live in the world where “post-truth” is a real word and alternative reality has spread far beyond the borders of the former Soviet Union. Whether it is covering the effects of Brexit on the NHS or politicians in Washington who now present “alternative facts,” reporting on lies is more than ever part of the job description of many journalists. And as journalists find their way in our post-fact, post-truth world, they should learn from the mistakes the Western media made in Ukraine.