The new US ambassador to Serbia arrives with a biography that stirs up old Balkan questions. Michael Yang, nominated by President Donald Trump, worked in 1996 as legal counsel to a congressional subcommittee that investigated how Iranian weapons were reaching the Bosnian Muslims via Croatia - during Bill Clinton's administration.

The claim comes from Sasha Jovicic, director of the organisation "Serbs for Trump," so it should be read with that caveat: it's a partisan voice, not a neutral source. But the historical event behind it is real. In April 1996, according to a Los Angeles Times report, Republicans led by Speaker Newt Gingrich launched an investigation into whether Washington had given quiet approval - a "green light" - for Iranian weapons to reach Bosnia.

The subcommittee then issued a report criticising the administration for the damage to diplomatic credibility and for the secrecy toward its own NATO allies. The case was compared to the Iran-Contra affair. Thirty years later, the very man connected to that investigation is arriving as ambassador in Belgrade - and it's hard to read that as coincidence.

For the region, this isn't just a personnel story. The choice of ambassador is a message about how Washington views the Balkans - which chapters it wants to open and which accounts are still open. Whether the appointment is a signal of a policy shift from the nineties, or just a symbolic move, will be seen from what Yang does, not from what's written about his past. But in the Balkans, where the past rarely stays past, details like these are never negligible.