It was never going to be easy for President Trump to bring an end to the Ukraine war, but it’s even harder when he’s operating under an erroneous theory of the conflict.

The man who instigated the war and who is the chief obstacle to peace is Vladimir Putin.

After a much-anticipated phone call with Putin on Monday, Trump sounded optimistic and said Ukraine and Russia will keep negotiating, although there was no indication of anything new.

After the browbeating he took in the Oval Office a few months ago and a pause in U.S. intelligence assistance, Ukrainian President Volodymyr Zelenskyy got the message. He’s done everything possible to portray himself as the reasonable one who’s interested in pursuing a deal.

A U.S.-proposed general ceasefire? Zelenskyy has said he’s willing to accept it. Russia’s idea for direct talks in Istanbul? Zelenskyy said he’d go himself.

He signed a critical minerals deal with the U.S.

Putin, in contrast, has been at the receiving end of an all-carrots approach, and has reacted accordingly.

Trump almost never strikes a pleading tone, but when Putin launched a large-scale strike on Kiev last month, Trump posted on Truth Social, “Vladimir, STOP!”

The play for the Kremlin is obvious here. It wants to keep inching ahead with territorial gains, and if it continues to string along negotiations, has to hope that Trump tires of the whole thing and cuts off U.S. aid to Ukraine. That would reward Putin’s intransigence with an important diplomatic victory — a split between the U.S. and Europe — and a chance to make major advances against an increasingly hard-pressed Ukraine.

Trump at times seems to realize this, and has referred to Putin “tapping me along.” But the master at establishing leverage in negotiations has failed to do so over Putin. In part, this is because the president has absorbed his MAGA base’s view that Putin isn’t really the problem — the Russian leader was baited into war by globalists who took insufficient account of Russia’s interests and feelings.

Whatever one thinks of the policy of NATO expansion, Ukraine didn’t invade Russia, and Putin’s opposition to Ukraine’s existence as its own independently governed nation is at the root of the war.

So long as Putin believes that he’s winning and holds “all of the cards,” there’s no reason for him to become more pliable. Trump and other administration officials have floated further economic measures against Russia, but these would probably be of limited utility. If the administration stipulated that if Putin doesn’t drop his maximalist demands — basically for a Ukraine that can’t defend itself — it will back Ukraine to the hilt, that might change his calculations.

Russia’s gains have come at a hideous cost — nearly a million Russian casualties since the start of the war. If Ukraine isn’t going to buckle and the U.S. isn’t going to abandon her, then the Russians could reach a point of exhaustion.

Short of that, Putin has every reason to think he can persevere when the world’s superpower has little sympathy for the victim of his unprovoked aggression.