Ten thousand protesters over the weekend poured into the streets of Yerevan, the capital of Armenia, defying the government’s crackdown. Russian-media reactions suggest the Kremlin is nervous, as Armenian President Serzh Sargsyan is a close Moscow ally.

The so-called Electric Yerevan protests erupted this month after the state utilities commission announced a 17% rise in electricity rates, and they have steadily grown. At issue isn’t merely the electricity price-hike in a country with 17% unemployment but the Russian domination...