In a Tbilisi courtroom, a Georgian judge on Thursday heard an appeal from the country’s third president, Mikheil Saakashvili, who is currently serving a six-year sentence on dubious charges.

The former head of state, emaciated and appearing to be in physical pain, addressed the court from a prison hospital and asked for permission to travel abroad to seek medical treatment.

A member of Georgian parliament from the former president’s political party, Khatia Dekanoidze, told me Mr. Saakashvili’s health has deteriorated since he was first imprisoned last October. “He has suffered from neurological disorders,” she said. She added that he is now only 170 pounds, which is dangerously thin for a 6-foot, 5-inch man.

Mr. Saakashvili’s humiliating fate is a grim reminder of what could happen to Ukraine’s charismatic president, Volodymyr Zelensky, were he to lose his country’s war against Russian aggression, or were America to lose interest in defending Ukraine.

Fifteen years ago, Mr. Saakashvili was feted in Western democracies much the way Mr. Zelensky is today. The former Georgian president helped to lead the Rose revolution in 2003, when thousands of citizens carrying roses stormed the parliament to demand new parliamentary elections.  

At the time, the civil resistance along with private American diplomacy pressured the Georgian leader, Eduard Shevardnadze, a former Soviet foreign minister, to accept new elections and step down from power. Mr. Saakashvili became the first non-Soviet leader of Georgia since it regained its independence in 1991 with the breakup of the evil empire.  

He soon went about implementing liberal reforms, opening up Georgia’s sclerotic economy to international investment and allowing a free and oppositional press. President George W. Bush visited Mr. Saakashvili in Tbilisi in 2005 and praised the Rose revolution as an inspiration “for others around the world who want to live in a free society.”

During Mr. Bush’s administration, the U.S. began training Georgia’s military, and it established a base in Georgia. In turn, Georgia volunteered troops to fight in both Iraq and Afghanistan. The homeland of Josef Stalin was now America’s ally.

Not everyone was pleased. In Moscow, the Kremlin launched a covert war of sabotage and terror against Mr. Saakashvili’s government that would eventually threaten the U.S. embassy in Tbilisi.

The tensions culminated in Mr. Bush’s last year in office, in 2008, when Russia baited Georgia into a war over the breakaway provinces of Abkhazia and South Ossetia. President Saakashvili, facing mounting attacks from Russian proxies in those provinces, attacked first, prompting a full Russian assault. To this day, Russian forces occupy Abkhazia and South Ossetia.

The Russian president, Vladimir Putin, had declared Mr. Saakashvili to be his personal enemy in 2008 and threatened to kill him. He did not succeed then, but eventually a Georgian billionaire who made his fortune in Russia, Bidzina Ivanishvili, established a new political party that eventually unseated Mr. Saakashvili’s party in 2013.

The new government under the sway of Mr. Ivanishvili launched a series of frivolous and corrupt prosecutions against members of the former government.

Unlike Mr. Shevardnadze, Mr. Saakashvili voluntarily left power after losing an election. He would move to Ukraine, where he became a citizen and was briefly governor of the Odessa Oblast.

At the same time, Mr. Saakashvili became a polarizing figure inside Georgia. Many of his original allies in the Rose revolution broke ties with his party.

A former national security adviser to Mr. Saakashvili, Giga Bokeria, told me, “Our ways have parted on fundamental political issues, but for me as a citizen of this country, having a former president as a political prisoner with risks to his life is a disaster.”  

Mr. Bokeria is not alone in this assessment. Earlier this week, Mr. Zelensky urged the Georgian government to allow Mr. Saakashvili to leave Georgia for medical treatment. The European parliament has issued a similar appeal for the former president’s release.

The U.S. government has not gone that far. Both the U.S. ambassador in Tbilisi and the State Department spokesman have said the Georgian government should provide Mr. Saakashvili with the medical and psychological treatment outlined in a report of independent medical experts commissioned by the country’s office of the public defender.  

Ms. Dekanoidze told me she was disappointed with the Biden administration’s response. “I think President Biden should say something personally,” she said.