During two decades as Russia’s leader, Vladimir Putin has rarely concealed his contempt for Western-style democracy and the rule of law. The poisoning of Russian political activist Alexei Navalny, amid a widening Russia-supported crackdown on opposition leaders in Belarus, indicates the lengths to which Putin and his cronies will go to silence their enemies and maintain power.

Russia’s forthright challenge to international norms demands a forceful Western response. It won’t come from the Trump administration, whose mild rebukes are consistently undercut by the president’s evident regard for Putin. In America’s absence, European leaders should develop a coordinated strategy to counter Russia’s threat to the continent’s stability and impose steeper costs for its misconduct.

The crisis in Belarus is the most immediate test. Five weeks since a fraudulent election sparked mass protests against President Alexander Lukashenko, the government has begun arresting and deporting leading opposition figures and opening criminal prosecutions against them. Putin has reportedly dispatched Russian operatives to assume control of Belarusian state media outlets and hinted at more forceful intervention if anti-government protests grow violent. Putin and Lukashenko, who met face-to-face on Monday, also seem to be exploring moves toward political integration — a form of "soft annexation” long sought by Putin, allowing him to extend Russian influence deeper into the heart of Europe.