From the opinion pages of the Wall Street Journal, this is Potomac Watch.

The U.S. says it believes China conducted a secret nuclear test in 2020, and President Trump reserves the right to follow suit,

as the Newstart Arms Control Treaty signed by President Obama is allowed to expire.

Meantime, the Food and Drug Administration summarily rejects an MRNA flu vaccine from Moderna,

but then under pressure, the FBI changes course.

Welcome, I'm Kyle Peterson with the Wall Street Journal.

We're joined today by my colleagues on the journal's opinion pages,

editorial board member Kate O'Dell and columnist Alicia Finley. The United States conducted its last

nuclear explosive test in 1992, underground at the Nevada test site. President Clinton then

signed the Comprehensive Test Ban Treaty in 1996, but it was rejected

by the Senate and never ratified. China similarly has signed but not ratified that treaty,

and now the Trump administration is saying in no uncertain terms that it believes Beijing has

recently done nuclear testing. Here's Assistant Secretary of State Christopher Yaw speaking last

week at a Hudson Institute event. As shared in Geneva, the United States government is aware

that China has conducted nuclear explosive tests, including preparing for tests with designated

yields in the hundreds of tons. China has used decoupling, a method to decrease the

effective effectiveness of seismic monitoring to hide its activities from the world. But the United States is paying close attention, and we are aware that China conducted one such yield-producing nuclear test on June 22nd, 2020. I have personally

examined the data, and I concur with the United States government assessment in this. As the

President has said, the United States will return to testing on a, quote, equal basis.

But equal basis doesn't mean we're going back to Ivy Mike style atmospheric testing in the multi-megaton range, as some arms control folks would have you believe hyperventilating about

this issue.

Kate, China may have denied any nuclear tests took place, but how do you read the importance

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