I was in Kyiv in September 2019 when Donald Trump’s infamous phone call to Ukraine’s President Volodymyr Zelensky became public — the one that led to his first impeachment. Witnesses said Trump pressured Zelensky to announce an investigation of Joe Biden to preempt his candidacy.

I was examining critical oil and gas pipelines and how Russia had been exerting its energy dominance over the more vulnerable Ukraine. The last thing Ukraine wanted was to become entangled in an American political campaign — especially when it needed U.S. weapons to fight Russia in the eastern part of its country.

Energy and the continuing conflict are closely linked. I wanted to interview Zelensky about his interaction with Trump.

That’s when I met Julia Mendel, Zelensky’s former press secretary. She told me the same thing she told everyone else — to go away. Ukraine had enough problems and didn’t need more. We have stayed friends, and she has connected me with sources for stories. Now, though, I’ve become her confidant.

She’s a true Ukrainian patriot. However, the war has drained her. She now advocates for a ceasefire so that Ukraine can rebuild its infrastructure — destroyed by Russian weapons. “Right now, our economy and democracy are collapsing,” she said. “The situation here is disastrous. The nation is collapsing. This is not freedom.”

Both sides have suffered heavy losses and injuries. Ukraine estimates that 750,000 Russian soldiers have been killed or wounded, and the war has devastated its economy; its national wealth is dedicated to the fight against Ukraine, while its oil and gas revenues are dwindling. Meanwhile, Russia confronts long-term economic challenges, including technological isolation, limited foreign investment, and a massive brain drain.

Ukraine reports that 43,000 of its soldiers have died in battle, with 370,000 others injured. The war has severely affected Ukraine’s economy, destroying its infrastructure and causing many to flee. Its industrial and agricultural industries have been devastated. The International Monetary Fund states that the war has driven millions into poverty.

Both sides are steadfast in their belief that they can outlast the other. Zelensky and his supporters believe that if they show any sign of weakness, Russia’s Vladimir Putin will pounce. Under President Joe Biden, the United States endorsed that thinking, emphasizing that Russia wants to consolidate its territorial gains. The European Union strongly opposes a ceasefire, fearing that Russia will set its sights on Poland and the Baltic states.

Nevertheless, all parties worry about the economic ramifications of a never-ending war, especially on energy costs.

This may be Russia’s weak link. Yale management professor Jeffrey Sonnenfeld points out that Russia depends on North Korean troops and Iranian drones to fight this war — not a good sign. And Putin’s military aims have nearly killed his country, arguing that the Russian economy is “imploding.”

To that end, oil and gas revenues have been propping up Putin’s regime — an asset running dry. Before the 2022 war, Russia provided 40 percent of Europe’s natural gas; now, it’s 10 percent. Meanwhile, the United States has stepped in to fill some of the gap, supplying 38 percent of Europe’s gas.

“Russia’s outright economic collapse appears far more likely now,” Sonnenfeld writes in a Yale periodical.  The Soviet Union partly collapsed in 1991 because the superpower had overextended itself, unable to keep up with its domestic and foreign obligations.

This is not the time to let up. With Western help, Ukraine can outlast Russia. Except for Hungary, Europe gets this, but does the United States get it? Trump has expressed his admiration for Putin. According to Sonnenfeld, Trump’s most prominent character trait is his fear of losing.

Indeed, historians praise Ronald Reagan for breaking the Soviet Union’s back and winning the Cold War. If Trump allows Putin to rebuild the dead Soviet Empire, history will never forgive him. He will never outlive the stench.

This will be a prolonged war, leaving both sides beaten down and beleaguered — hard to stomach but necessary to teach Putin a lesson.