Michael Haltzel, a senior fellow at the Center for Transatlantic Relations of Johns Hopkins University’s School of Advanced International Studies, was European policy adviser to then-Sen. Joseph Biden from 1994 to 2005.

While the United States understandably focuses on the Middle East and Central Asia, democracy in Bosnia and Herzegovina, once considered a rare transatlantic success story, is in danger of unraveling.

The 1995 Dayton accords that ended Bosnia’s three-year bloody war did not quell the virulent disagreements among the country’s three largest nationalities: Bosniaks, Serbs and Croats. Moreover, Dayton bequeathed Bosnia a dysfunctional and excessively redundant constitutional structure. The international community’s representative to Bosnia noted a few years ago that the country of 4 million people has “two entities [for] three constituent peoples; five presidents, four vice presidents, 13 prime ministers, 14 parliaments, 147 ministers and 700 members of Parliament.”

Nonetheless, in the first decade after the war, Bosnia made notable progress. It even attempted in 2006 to reform its constitution. But after that initiative failed by two votes, interethnic relations and, indeed, governance went into steady decline.

The European Union, eager to atone for its fecklessness during the war, persuaded the United States to end its peacekeeping role. An E.U. force replaced the United Nations’ blue helmets, and the Americans went home. Although a succession of E.U. officials has tried to induce the feuding groups to cooperate, it has become increasingly clear that, successful or not, Brussels is determined to close the office of the international high representative and to wind down its own political and peacekeeping involvement in Bosnia.

A lawsuit that two Bosnian citizens took to the European Court of Human Rights has brought the situation to a crisis point. In 2009 the court found that certain provisions of Bosnia’s constitution and election laws discriminate against minorities. Bosnian civil society groups and international human rights organizations rejoiced, expecting swift remedial measures as the European Union, to which Bosnia aspires, made amending the constitution and electoral laws a condition for membership. But nearly three years later, the ruling is being turned on its head as part of a backroom deal.

In late July the Social Democratic Party, which garnered the largest number of votes in the 2010 parliamentary elections while running on a secular, multiethnic platform, abruptly pulled out of a coalition with the Party of Democratic Action, the principal standard-bearer of Bosniak Muslims. The Social Democrats formed an electoral alliance with HDZ, the largest Bosnian Croat party. Advertised as a positive response to the court ruling, the deal is actually the opposite, as it reinforces Bosnia’s growing ethnic and religious tribalism.

The draft electoral law, included in a complex set of constitutional amendments, would lock in representation of each of Bosnia’s three constituent peoples in areas where they compose a majority at the expense of the “others” — Roma, Jews, other ethnic minority citizens and the large number of Bosnians who choose not to identify with any single ethnic group. The Bosnian Croats living in areas governed by the HDZ would be most favored, receiving a virtual veto over national legislation. This division of spoils would be especially inequitable since Bosnia’s next census, in 2013, is expected to show that the country’s “others” group is as least as numerous as the Bosnian Croat community. The leader of the Serb entity, Republika Srpska, sees the law as furthering his own separatist ambitions.

Opposition to the draft law has been furious. The Croat member of the country’s tripartite presidency, whose family — like those of many Bosnian citizens — transcends ethnic and religious lines, resigned from the Social Democratic Party in protest. The two minority citizens who brought the 2009 court case publicly came out against the draft law, as did the largest Bosniak party. Civil society organizations are mobilizing to defeat the legislation, slated for a vote in the coming weeks. In early August the groups wrote to U.S. lawmakers, likening the legislation to the three-fifths counting of slaves that preceded the 14th Amendment and asking for support to defeat it.

One would expect the European Union, which is never shy about extolling its commitment to “European values,” to support the opposition. But E.U. officials have watered down standards for implementing the court’s decision to making a “credible effort” to do so. The United States, reluctant to undermine transatlantic cooperation that has been fruitful elsewhere in the Balkans, appears willing to defer to Brussels.

It is difficult to see how this electoral law would enhance stability in Bosnia. Cementing the power of ethnic fiefdoms runs directly against the tide of 21st-century European history. Cutting large segments of the population out of meaningful political participation will exacerbate tensions, not foster a unifying attachment to the state.

The contrast with two of Bosnia’s neighbors could not be greater. NATO member Croatia will join the European Union next year. Montenegro, which has integrated large Albanian and Slavic Muslim minorities into its national life, reached the negotiating stage of its E.U. membership in June and is well on its way to joining NATO.

Meanwhile in Sarajevo, political life revolves around shabby agreements among party bosses, and the country’s larger interests, including its NATO and E.U. candidacies, languish. Bosnia and Herzegovina, whose citizens have suffered so grievously and in which the United States and its allies have committed significant resources for two decades, presents a sorry spectacle.