Georgian opposition leader arrested, deepening the political crisis in the South Caucasus country

The unrest is the latest upheaval along Russia’s vast borders: Protests continue in Belarus over an August presidential election result that the opposition has denounced as fraudulent, and Kyrgyzstan recently had its third revolution in the past 15 years.

Georgia, a country of about 3.7 million people bordering the Black Sea, was considered more democratic than the other two, with ambitions to join NATO. But Tuesday’s escalation could ultimately work to Moscow’s benefit, potentially alienating Tbilisi from its powerful Western allies. In recent years, U.S. lawmakers have expressed concerns in letters to Georgia’s leadership that some actions by the ruling Georgian Dream party indicated a “backsliding.”

Billionaire oligarch Bidzina Ivanishvili, the founder of Georgian Dream,…