President Joe Biden’s dramatic train trip through a war zone to stand with Ukrainian President Volodymyr Zelenskyy in Kiev inspired most of the world, but not everyone. Vladimir Putin’s Kremlin hacks, who ardently wish not to join the thousands of Russians thrown into jail for opposing the former KGB agent’s corrupt autocracy, did not applaud Biden’s trip. Neither did America’s MAGA set, led by Putin fanboy Tucker Carlson and others who are either looney or have lost their way. But most Americans saw Biden’s unprotected trip through an area vulnerable to Russian missile attacks at any moment as a brave, historic move, one intended to physically demonstrate our solidarity with the Ukrainian people, who are suffering mass death and horrific hardship in order to resist subjugation by a brutal Russian regime.

Biden was greeted in Kiev by the man who exemplifies Ukrainian courage in the face of relentless Russian war crimes. When the Russians invaded Ukraine a year ago, no one bet on Zelenskyy remaining alive, let alone walking the streets of his country’s capital. It is in no small measure thanks to Zelenskyy’s ability to inspire Ukrainians and non-Ukrainians alike that his country was able to repel Russia’s designs in Kiev and is holding the line against brutal assaults in the east. And he has exposed Putin as a tyrant, a war criminal and a crook.

But as for exposing Putin, someone else got there first, and he sits, deteriorating and perhaps dying, in a Russian cell, condemned to spend what may be the rest of his life there as a consequence of his own courage. Indeed, it isn’t easy to imagine anyone more courageous than Alexei Navalny, the Russian anti-corruption activist and opposition leader whose condemnation of Putin’s corruption and resourceful organizing against Putin’s kleptocracy resulted in sham criminal convictions and confinement in harsh conditions that will not end as long as Putin is in power.

Navalny, whose criticisms of Putin focused undesired attention on the embezzlement-prone despot, made a documentary exposing Putin’s ripoff of his people, entitled “Putin’s Palace.” After previous attempts to assassinate Navalny failed, agents of Putin’s Federal Security Service poisoned him in Siberia in August 2020. Navalny nearly died, and the Kremlin was extremely displeased that he did not. Instead, a German charity spirited the dissident, near death, to Berlin, where he was miraculously nursed back to health.

While in Germany, Navalny had the notion that he could get one of the Russian agents who had poisoned him to admit that he had done so. It worked -- and Navalny played the tape containing the admissions to an international audience.

But that wasn’t all. Knowing that he would be arrested upon his arrival and sent to prison, Navalny nevertheless then boarded a flight home to Moscow -- where he was arrested upon his arrival and sent to prison. That is where he sits, and that is where he may very well die.

HBO and CNN teamed up to produce a documentary about all of this, called “Navalny,” in which one can watch as, with minimal effort, Navalny induces a Russian goon to confess the poisoning, and as he then returns to Moscow on his mission to draw attention to Putin’s tyranny. “Navalny” is up for an Academy Award on March 13. As his daughter told The New York Times’ Nicholas Kristof last week, Navalny’s family and supporters hope the documentary is his “get out of death card,” one which will garner so much attention that Putin will feel obliged to keep her father alive rather than slowly kill him.

Back in America, the likes of Ted Cruz mock support for Ukraine. “A Ukrainian flag has become like a COVID mask,” Cruz said last week. “It’s a sign to show your virtue.” Some become heroes. Some become hacks. History has a way of judging these things.

Jeff Robbins, a former assistant United States attorney and United States delegate to the United Nations Human Rights Council in Geneva, was chief counsel for the minority of the United States Senate Permanent Subcommittee on Investigations. An attorney specializing in the First Amendment, he is a longtime columnist for the Boston Herald, writing on politics, national security, human rights and the Mideast.