Opinion | Bosnia Is on the Brink of Breaking Up

In the 1990s, the West was slow to react to the breakup of the former Yugoslavia. After much bloodshed, it eventually launched airstrikes against the Serb forces in Bosnia in 1995 and in Serbia and Kosovo in 1999, and deployed tens of thousands of NATO troops to oversee the truce and stabilize the region. In subsequent years, the United States and the European Union spent billions of dollars to help reconstruct the region. Though often justifiably criticized for focusing on short-term, slapdash solutions, their efforts were key to ensuring the safety and stability of the Balkans.

But their attention slipped away. The United States, more focused on its operations in Afghanistan and Iraq, had withdrawn from hands-on engagement by 2010. It handed over the responsibility to the European Union, which was supposed to underwrite the region’s long-term stability by accepting its countries into the bloc. Yet by 2019, as the European Union struggled with its own problems and divisions, it became clear that the offer had been effectively taken off the table.

Robbed of their European dream and denied full access to the bloc’s common market, Balkan leaders reverted to the nationalism and populism of the past. The rule of law, human rights and other key democratic principles fell by the wayside. In multiethnic countries with unfinished national projects, such as Bosnia, Montenegro, North Macedonia and Kosovo, ethno-political divisions have festered.

Even so, the main responsibility lies with the countries themselves, especially political representatives and their affiliated media, who based their popularity on spreading animosity toward other ethnic groups. In Bosnia and Herzegovina, ethnonationalism has taken center stage. Mr. Dodik is not alone in his radical ways: Muslim Bosniaks, the largest ethnic group, have agitated for a unitary state, and Bosnian Croats have demanded an autonomous Croat region.

Crucially, the abdication of the West not only allowed democratic backsliding but also opened the region to other outside forces. Russia has taken a pronounced interest, establishing a strong political influence in all Serb-populated parts of the region, while Turkey, the Gulf countries and Iran have done the same in Muslim-populated areas. China, using its political pragmatism and ample economic resources, has become a major presence throughout the region. What’s more, Croatia and especially Serbia have started to interfere in the internal politics of neighboring countries, adding to regional tensions.