As he often does, former Defense Secretary Robert Gates succinctly summarized the Ukrainian crisis, telling CNN’s Fareed Zakaria “Our long holiday from history is over.” He should know, having long shaped the structure that suddenly collapsed when Putin savagely invaded an inoffensive, neighboring republic. In a flash, seven decades, innumerable precedents, conventions, untold trillions in defense expenditures, and a pervasive sense of peace vanished in the roar of missiles reaching their targets.

The burning question: How long could the courageous but over-matched Ukrainians hold out before Admiral Nelson’s famous dictum caught up? “Numbers annihilate.”

But from the conflict’s first hours, Ukrainian fighters seemed determined to walk a hero’s path running from Bastogne and the Alamo back to Thermopylae. Thirteen Ukrainian border guards achieved immortality when their wonderfully obscene response to a Russian warship quickly galvanized global websites. There were startling reports of Russian transports being shot down, of armored columns ambushed and destroyed. Yet even as the bristling combined arms force bore down on him, Ukrainian President Vlodymyr Zelenskiy provided a classic demonstration of courage under fire, coolly dismissing an American attempt to evacuate him. “I need ammunition, not a ride!”

Defying early assumptions of Russian cyber-war, the global info-sphere instead carried resounding messages praising Zelensky and his embattled cohorts, while universally condemning Soviet-style aggression. That’s the thing about genuine heroism: Its blinding light immediately reveals and shames anything less. That is why, as the war grinds into its second week, Vladimir Putin is in real trouble. Not only has the outside world turned against him - the ruble plunging to all-time lows - but internal dissent is growing, thousands of peace demonstrators arrested on the streets of Moscow and St. Petersburg. A star Russian athlete even used his television time to write “No war, please” on the camera lens. Were these people no longer afraid of the gulag and the dreaded secret police?

Far more serious was Putin’s chilling announcement that Russian nuclear forces had been placed on high alert. Was this anything more than an obvious intent to intimidate, invoking the nuclear genie to distract from Russia’s lack of progress on the ground? If so, it didn’t deter Germany - Europe’s center of gravity - from announcing that it would now support the Ukrainian resistance with anti-tank and antiaircraft weapons. Berlin’s stunning reversal - from what had been a deeply ambiguous neutrality - may have been a mortal blow to Putin’s reputation for winning by intimidation. With growing diplomatic and economic reversals now added to military ineffectiveness, there were immediate questions about the strongman’s own survival. Senior American officials like Condoleezza Rice were even wondering about Putin’s mental stability.

So is he crazy or just incapable of making sound decisions? Either way, one looked for answers from Russian history, where popular “elections” mostly ratify previous decisions of the ruling elites. So it was that Nikita Khrushchev, in October, 1962, boldly gambled and placed Soviet missiles in Cuba: but he was forced to withdraw them when confronted by President Kennedy, backed by American military might. Not many months later, Khrushchev was gone, quietly replaced because of his “adventurism” in Cuba. So why should Putin’s fate be any different?

That answer may well depend on the battles now immediately before us. Russia can reinforce its advantages in armor, artillery, hyper-baric rockets and long-range fires to trash major population centers like Kharkov and Kiev - all of it viewed in exquisite detail by an aroused global audience. NATO countries on Ukraine’s borders can reinforce the resistance by covert infiltration routes - also subject to Russian counter-attacks and increasing risks of escalation. The courageous persistence of Ukrainian fighters has already been established: but how long before Nelson’s Law takes effect? Can they win a longer insurgency?

It is a dangerous time, perhaps our most perilous since the Missiles of October, but there is no conceivable way of turning back. Watching these events unfold over this momentous weekend, I kept comparing Putin to the mad Inspector Javert from “Les Miz.” A single tune kept replaying in my mind and perhaps you heard it too:

Do you hear the people sing?

Singing a song of angry men?

It is the music of a people

Who will not be slaves again!

NOTE: Colonel Allard is the author of Command, Control and the Common Defense, winner of the 1991 National Security Book Award. After leaving active duty, he became an on-air military analyst for the networks of NBC News