ITV News Senior International Correspondent John Irvine reports from Mariupol, in the Donetsk region of Ukraine
His latest strengthening of their resolve was that diatribe of insults broadcast from the Kremlin on Monday night.
Ukrainians are proud of the country about Mr Putin was absolutely scathing. He was as offensive as you can get without resorting to swear words.
He keeps claiming that Ukraine is guilty of genocide against the pro-Russian people living in the self-proclaimed people’s republics he has just officially recognised.
It’s nonsense. The Ukrainian army has been restraining itself in the face of provocative fire from the other side of the line of control.
Essentially the pro-Russian separatists have had free shots.
The Ukrainians are now mobilising their reservists. If it comes to it, they can muster up to 2.5 million fighting men and women.
If the Russian army invades it will initially enjoy a four to one advantage in terms of respective troop numbers. Then might come an occupation and an insurgency.
Historically, the Ukrainians have been highly effective partisans when they have to fight invaders. Just ask the Wehrmacht and the Red Army, neither of which could defeat them between 1941-45.
In his rambling address, Mr Putin suggested that Russia and Ukraine should never have divorced after the collapse of the Soviet Union. Now he wants to force a re-marriage.
But for most Ukrainians his country is not an attractive partner. Mr Putin leads a country where people are struggling economically.
Neither do the two ‘republics’ he has just recognised bode well for a Russian takeover of all Ukraine.
They are bad joke post-Stalinist police states, where most of the coal mines and factories now lie idle.
The standard of living is so low that around 1.5 million Ukrainians have fled since they came into existence in 2015.
To win that war the pro-Russian separatists – and disguised elements of the Russian army – had to win the battle for Donetsk airport.
The Ukrainian soldiers defending the airport put up legendary resistance for eight months. They were such resolute fighters they were nicknamed ‘the cyborgs’.
Boris Johnson is among those who has predicted that if it comes to it the Ukrainians will fight. History suggests he’s correct.
Of late, a joke of sorts, has been told on a social media network used by the Ukrainian army. It suggests that Russian soldiers invading Ukraine come with the seeds of fruit trees in their pockets. The inference is that they will end up dead and buried in Ukraine and that the only good to come of it will be fruit trees growing from their graves.