BELGRADE – Vice President Joe Biden makes the highest-level U.S. visit to Serbia in a quarter century this week seeking a new diplomatic start in the Balkans, a region where Washington twice intervened militarily in the 1990s.

In visiting two of Serbia's former adversaries, Bosnia and Kosovo on the same trip, the former U.S. senator with much experience in foreign affairs faces a tricky balancing act where sensitivities about the past wars and divisions remain strong.

The main point really is that, in a sense, the United States is back; the focus that we had in the 1990s on the region is back, a senior U.S. official told reporters.

We haven't been as focused on the Balkans in recent years, maybe some of the momentum, for example, in Bosnia, has been lost or, in some cases, reversed.

In 1991 just before the start of the wars that ended Yugoslavia, then Secretary of State James Baker said: We don't have a dog in this fight. But by 1995 Washington and NATO were bombing Bosnian Serbs and then brokering a peace deal to end a war that killed 100,000 people.

In 1999, the United States and NATO bombed Belgrade in an effort to force rump Yugoslavia to withdraw from Kosovo. A few major buildings in the Serbian capital Belgrade remain in rubble and resentment over the bombing endures.

In recent years, the United States has focused on Kosovo, which declared independence last year, after devoting much attention on warring and postwar Bosnia in the mid 1990s.

We have had an approach in the last 20 years where we have tried to address what we see as the most critical problems, U.S. Ambassador to Serbia Cameron Munter said in an interview. What that sometimes leads to is a focus so that those problems sometimes become the defining element of the Balkan policy.

Washington now seeks a broader view of interlocking Balkan issues, he said, a region hoping to join the European Union.

THREE DAYS, THREE COUNTRIES

The vice president arrives on Tuesday in Bosnia, where he meets leaders from both halves of a country divided along ethnic lines. The Bosnian Serb half has acted more assertively since 2006 on boosting its autonomy and the Muslim-Croat half remains stuck in a political and economic morass.

What the problems are here is a clear demonstration that appeasement does not work, said Raffi Gregorian, a U.S. diplomat who is the deputy peace envoy to Bosnia. Messages of keep Bosnia quiet but don't do anything have not succeeded on behalf of the international community.

Highlighting the division is an announced protest during Biden's visit by Serb veterans to draw attention to what they call discrimination of non-Muslims in Bosnia. Diplomats and analysts say the ethnic standoff could endanger the entire region's stability and slow EU integration.

Bosnian Serbs are wary about Biden visit and a big U.S. role, but Bosnia's foreign minister welcomed him.

It is a very clear sign of the willingness of this new administration to engage in Bosnia-Herzegovina, to finalize the project that was started during the Clinton Administration, Sven Alkalaj told Reuters.

Serbs in particularly are watching Biden skeptically because of his past criticism of Serb actions in Kosovo, its ex-province that remains a sore point in relations with the West. Biden, who visits Belgrade on Wednesday, is the highest-ranking U.S. official to Serbia since Vice President George Bush in 1983.

By contrast, Biden is likely to receive a warm welcome on Thursday in Kosovo, where he is celebrated as a long-time supporter of Kosovo independence during his years as a U.S. senator. Kosovo is strongly pro-American and the capital Pristina has a Bill Clinton Boulevard and will soon rename one of the city's street after George. W. Bush.

The vice president also had a family link to Kosovo. His son Joseph III, now Delaware's attorney general, served as a U.S. Justice Department adviser in Kosovo in 2001.

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