The Federal Reserve has a problem that no interest-rate decision can solve cleanly: the policies threatening US growth are also threatening to push prices higher.

On June 18, the Fed kept its benchmark interest-rate target at 4.25%-4.50%, leaving rates unchanged for a fourth consecutive meeting.

Normally, the decision would be relatively straightforward.

If inflation is too high, raise rates.

If growth is weakening, cut them.

But tariffs complicate the equation.

Higher import tariffs can increase the prices American businesses pay for foreign goods and components. Companies may then pass those costs on to consumers.

That creates inflationary pressure at exactly the moment when weaker trade and investment could slow economic growth.

The Fed therefore has to choose between two risks.

Cut rates too early, and tariffs could feed into inflation before price pressures are fully under control.

Keep rates high for too long, and borrowing costs could weaken investment, housing and consumption.

The Fed's own June projections captured this tension. Policymakers projected 1.4% US GDP growth for 2025, alongside 3% PCE inflation, while the unemployment rate was projected at 4.5%.

The inflation number is particularly important.

The Fed's long-run inflation target is 2%. A projected 3% inflation rate would therefore leave policymakers with considerably less room to cut rates aggressively.

Yet policymakers still projected two rate cuts by the end of 2025.

That sounds contradictory until you consider the timing problem.

Monetary policy works with a lag. A rate cut today does not instantly increase consumer spending or business investment. It can take months for cheaper borrowing to work through the economy.

The Fed therefore has to make decisions based partly on where the economy is heading, not simply where it is today.

This is why tariffs have created such a difficult policy environment.

A traditional recession can often be fought with lower rates. A traditional inflation shock can be fought with higher rates.

A supply shock that weakens growth while raising prices gives central banks a much uglier choice.

The real test for the Fed is whether tariff-driven inflation remains temporary. If it does, rate cuts become easier. If it does not, the world's most important central bank could be forced to keep borrowing costs high even as growth slows.