Most believe his view of the war has been shaped by his numerous and lengthy interactions with Vladimir Putin, the Russian President, who believes his side is nearing victory.
But there are always two sides to a story.
From Kyiv’s perspective, its armed forces have headed off a long, brutal offensive operation by Russia.
Moscow has lost close to 1000 men – killed or wounded – every day for months on end, according to Ukrainian estimates, which are often cited by Western intelligence agencies.
The total number of Russian casualties stands at 1,104,500 since the beginning of the full-scale invasion on February 24, 2022.
It’s a high price considering Moscow has managed to capture only 0.5% of Ukraine’s total territory since the beginning of this year.
There have, of course, been tricky moments for the Ukrainians in that time, such as when Russia broke through on the eastern front lines towards the Donetsk region garrison town of Pokrovsk.
Moscow’s men marched forward 14.5km in a matter of days, in the period before the US-Russia summit in Alaska.
Like other offensives, that shock advance has been brought under control by Ukrainian special forces units sent to quash it.
On Wednesday, Zelenskyy told Trump that his forces had encircled at least 1000 Russian soldiers.
The Ukrainian President didn’t say where, at least publicly, but he could have been referring to the liberation of territory in the direction of Dobropillia.
After their talks in New York, DeepState, a Ukrainian war-monitoring group with ties to the Defence Ministry, updated its battlefield tracking map to show a Ukrainian advance directly through the Russian salient in the area.
The map shows a distinctive red patch, marking Russian control, surrounded entirely by Ukrainian-held territory near the tiny village of Kucheriv Yar.
A few kilometres south on the same salient, Ukraine is said to have recaptured the village of Nykanorivka.
It often takes days for battlefield maps to catch up with reality, meaning Ukrainian forces could have once again sliced through the Russian bridgehead, leaving a portion of enemy forces surrounded.
Small success stories like this add up.
Zelenskyy was able to tell Trump that his forces had liberated 580sqkm of Ukrainian territory in September alone.
At the same time, pro-Ukrainian analysts are sharing details of what they claim to be evidence that Russian desertion rates have doubled.
Russian war bloggers are also appearing to be more gloomy in their social media musings.
Those who know the US President the best sometimes say it’s good-news stories like these that affect his thinking the most.
But it was perhaps another Ukrainian military mission far from the front line that swayed Trump the most.
Since the start of August, Kyiv has stepped up its long-range strikes against Russia’s oil refineries.
At least 16 of Russia’s 38 refineries have been hit in that time alone, triggering fuel shortages and sending exports plummeting.
The campaign has disrupted Russia’s processing capacity by at least a million barrels a day, according to Energy Aspects, a research group.
“Once the number of drones matches the Russians’, they will feel the fuel shortage and loss,” Zelenskyy recently told reporters in Kyiv. “We already see this increasingly. More drones are reaching targets.”
With exports down, the Kremlin is losing out on the funds it needs to fuel the war in Ukraine.
Fuel shortages and spiralling prices also appear to be biting, with pictures emerging of closed filling stations or long queues for those still open.
Russia’s far east and occupied Crimea were the first territories to experience shortages, according to a report by the Reuters news agency.
Similar problems have emerged in the Volga River region, as well as in southern and central Russia.
In recent days, unverified video footage has emerged on social media purporting to show queues forming outside a petrol station on the highway between Moscow and St Petersburg.
Ukrainian officials believe public discontent will force Putin to the negotiating table.
Targeting Russian fossil fuel exports has been a key strategy for Trump. He has slapped India with extra trade tariffs because of its purchase of cheap Russian crude oil.
The European Union has also promised to speed up its embargo on Russian fuel imports under duress from the White House.
In his own eyes, it is a clear demonstration that Trump’s strategy is starting to pay dividends. And for Ukraine and Europe, a happy US President is a good one.
There are weapons America controls solely, such as the Patriot air-defence system or Himars rocket launchers, which Ukraine desperately need.
Mark Rutte, the Nato Secretary-General, has negotiated a deal with Trump to ensure a pipeline of this kit remains open, as long as European allies fund it.
This, for now, is working, with almost US$2 billion pledged by European governments for the scheme.
That figure is expected to rise to US$10b in the near future, and Zelensky has said that it could increase to US$90b if Ukraine gets its way.
Some of the sales agreed by the US include thousands of long-range, air-launched cruise missiles worth almost US$1b.
Crippling Western sanctions and a lack of funds will make it harder for Russia to rearm at the same rate.
Russia’s economy has taken a hit since Putin launched his invasion in February 2022, with the rouble still floundering below its pre-war high against the dollar.
Official GDP forecasts this year have been revised down from 2.5% to 1%, while the budget deficit has grown to US$50b and is expected to rise further this year, exacerbated by the drop in exports.
On top of foreign imports, Ukraine is betting on its own domestic manufacturing boom to make up for a lack of genuine US support.
Technological advances in the past 3½ years have enabled Kyiv to produce drones at huge volume.
And then there are other projects, such as the domestically produced Flamingo cruise missile. On paper, it can fly for more than 2900km and carry a one-tonne payload.
Its effectiveness, however, remains a mystery because of limited battlefield tests.
During their infamous Oval Office spat, Trump told Zelenskyy that he didn’t hold the cards “right now”.
While a genuine military victory might remain a fantasy scenario, Ukraine’s President has been quietly improving his hand.
And it’s one he, and perhaps now Trump, believes could prevail if given the time and support from international allies.
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