The border that divides Canada and the US is the busiest in the world. Before the pandemic, it saw 400,000 crossings and about $2bn (€1.7bn) worth of goods and services pass over it every day. So closing the border to all but essential traffic in March to curb the spread of coronavirus was a delicate piece of diplomacy between Ottawa and Washington.

“The magnitude of this decision can’t be underestimated,” says Kirsten Hillman, Canada’s new ambassador to the US, who formally took up her post just days after the border restrictions came into force. “To implement it that quickly was exceptional and surprising – that you could do something of such great magnitude at such speed. In those early days of the pandemic, governments were having to make really impactful decisions really quickly,” Hillman adds, speaking from Canada’s embassy in Washington. “All that was happening in an environment of less-than-perfect information.”

The role in Washington is the most prized ambassadorial posting for a Canadian as the US is the country’s largest trading partner and represents its most significant diplomatic relationship. It’s a partnership that has been strained during Donald Trump’s tenure as president. “My responsibility is [to make] sure that relationship is effective and that we are understood down here,” says Hillman.

Her expertise in trade has informed her approach to her new role. “I’ve spent my career as a trade negotiator and a trade lawyer,” she adds. “My job is to elucidate the facts: to advance and defend the interests of Canada; to promote the ways in which we, working with the US, can achieve more, and do things better, than when we are working alone.”

An anniversary that has previously proved divisive for neighbours Serbia and Croatia has this year provided an opportunity for a more cordial relationship. Croats view Operation Storm as the military masterstroke that won the Homeland War in 1995. Serbs see it as the worst act of ethnic cleansing in the 1990s.

But on the 25th anniversary in August, Croatia’s prime minister Andrej Plenkovic (pictured) publicly condemned war crimes committed by Croatian forces as a “painful ugly scar” and promised to help displaced ethnic-Serb families to return home.

Plenkovic’s victory in July’s parliamentary election endorsed his policy of steering his hdz party away from right-wing nationalism. Improved relations with Serbia would be a significant dividend.

With 57 participating states from Europe, Asia and North America, the osce is the world’s largest regional security body. Former governor of Virginia, James Gilmore began his career as a US agent in the 1970s. He took up this post in 2019. 

What is your current focus?
The central issue at the moment is Ukraine. The aim of the osce is to supply its monitoring mission and to find a way to implement the Minsk Agreement, so that this conflict [between Russia and Ukraine] can be brought to an end. And the political situation in Belarus is also a primary issue, which can only be resolved through fair and free elections.

What are the security challenges in the region that you’re trying to address?
The principal challenge is the Russian Federation, which has decided to aggressively push forward in places where they shouldn’t be – in Georgia and Ukraine. Crimea is a serious problem – an attempt to annex another country’s territory by force is a violation of the Helsinki Accords, which form the basis of the osce. But we’re in touch with the Russians and trying to find common ground.

You’ve recently said that you are embarrassed by recent calls from experts to normalise ties with Russia. What is your position?
Russia cannot be permitted to enjoy the benefits of normalised relations when it is misbehaving in so many places. To send the message that all is forgiven is the wrong thing. Russia needs to adhere to the Helsinki Accords and the principles of non-aggression in Europe and Asia.

In a new regular feature, we take a look at a case of diplomacy gone wrong. 

Who vs who: Nigeria vs Ghana

What it’s about: The treatment of Nigerian nationals living in Ghana. A Ghanaian association of retailers has been leading a campaign against Nigerian-operated businesses – in some cases destroying them.

What it’s really about: The two countries are long-term rivals. Ghana has laws against foreigners – including Nigerians – owning retail businesses  and has recently stepped up enforcement. Earlier this year, Ghana apologised after a building in a Nigerian compound was bulldozed by armed intruders acting on behalf of a local businessman.The two governments are speaking to each other but this is at least as likely to escalate matters as it is to soothe tensions.