In a world of economic uncertainty, there's some certainty this morning. President Trump's sweeping new tariffs are, as of now, in force.

I'm David Brancaccio in Los Angeles. It is now a world where U.S. import duties more than double the cost of goods coming from China.

The now escalated China tariff is 104%. The U.S. has added hefty duties to goods

from allies as well. The EU 20%, Japan 24%. While U.S. stock index futures are down moderately,

minus 6 tenths percent for S&P futures now, it is the bond market that's quite unsettled this morning.

The U.S. government bond fell sharply overnight, pushing

up the benchmark 10-year interest rate for a time close to 4.5%. Marketplace's Nancy Marshall-Genzor

is here with more. Hey, David, investors sold off U.S. Treasury bonds in just a wave starting on Monday,

so price is tanked. And when that happens to bonds, it means

yields the interest rate on bonds go up. In other words, when prices are down, the U.S.

government has to offer a higher interest rate to attract investors. One key factor there,

inflation fears with tariffs making things more expensive in the U.S. What else?

Yeah, there are a number of theories here. One is investors like hedge funds had to sell bonds

because they borrowed money to buy stocks. As you know, stocks have plummeted. So now those

investors are caught short and are selling bonds to raise cash. Another theory is there will be less global trade in dollars because of the tariffs.

Citibank analysts told Reuters those dollars tend to find their way into U.S. treasuries.

So with fewer dollars around, there will be less demand for U.S. bonds.

All right.

And the 10-year interest rate is, of course, a gauge on what

consumers pay for money that we all borrow. Yes, it is. Mortgage rates are loosely tied to the 10-year

treasury bond rate. They do tend to move together. So if bond yields surge higher, so do mortgage rates.

Bond rates can also affect the rates on other types of borrowing,

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