For Zambia, a rise in US government bond yields is more than a Wall Street development. It can influence how expensive it becomes for the country to borrow abroad, how investors price Zambian assets and how much pressure the kwacha faces against the dollar.
The yield on the US 30-year Treasury rose to around 5.44% on Thursday, its highest level since 2004, while the benchmark 10-year yield climbed above 5.1%.
The move matters because US Treasury yields form a reference point for borrowing costs across much of the global financial system. When those yields rise, emerging markets such as Zambia can face higher financing costs even when their own domestic interest rates have not changed.
The immediate trigger was a combination of stronger-than-expected US economic activity, expectations of further Federal Reserve tightening and rising oil prices.
For Zambia, however, the bigger question is what a prolonged period of higher global interest rates means for a country still rebuilding its fiscal and external position after years of debt stress.
Why Zambia should pay attention
US Treasury securities sit at the centre of the global financial system. They are widely used as a benchmark for pricing other forms of debt.
When Treasury yields rise, investors can demand higher returns from riskier assets as well.
For an emerging market such as Zambia, that can increase the cost of accessing international capital.
A Zambian government or company seeking to borrow in international markets does not compete with US Treasuries on equal terms. Investors generally demand an additional risk premium for lending to countries perceived to carry greater economic, currency or credit risk.
If the underlying US interest rate rises, the overall cost of borrowing can therefore increase even if Zambia's own risk premium remains unchanged.
The dollar channel
Higher US yields can also make dollar-denominated assets more attractive to international investors.
That can contribute to capital moving towards US markets and away from some emerging markets.
For Zambia, movements in the dollar are particularly important because much of the country's external debt and international trade is denominated in foreign currencies.
A stronger dollar can increase the local-currency cost of servicing dollar-denominated obligations and make imports more expensive.
The effect is not automatic. Exchange rates also depend on copper export receipts, domestic monetary policy, foreign-exchange supply and demand, inflation and investor confidence.
Copper provides a counterweight
Zambia has an important advantage that many emerging markets do not: copper.
Strong copper prices can increase export earnings and foreign-exchange inflows, providing support for the kwacha and improving the country's external position.
But copper cannot completely shield Zambia from global financial conditions.
If international interest rates remain elevated, investors may still become more selective about emerging-market assets. The country can therefore benefit from stronger commodity revenues while simultaneously facing a more expensive global financing environment.
The debt lesson
The latest Treasury move also underlines why Zambia's debt restructuring is only one part of the country's long-term financing challenge.
Even after restructuring, future borrowing will be priced against prevailing international interest rates and the risk investors attach to Zambia.
This makes fiscal discipline, export earnings, foreign-exchange reserves and the credibility of economic policy important determinants of future borrowing costs.
For policymakers, the implication is straightforward: Zambia cannot influence the Federal Reserve, but it can influence how exposed the country is to changes in global financial conditions.
The rise in US Treasury yields is therefore a reminder that Zambia's economic fortunes are shaped not only by what happens in Lusaka or Copperbelt mining towns, but also by decisions made in Washington and movements in global capital markets.
When the price of money rises in America, emerging markets eventually feel it — and Zambia is no exception.
