But in the premium bond idea, the government would renew old, expiring bonds at higher coupon rates. Doing so would not technically add to the nation’s debt — if the government previously had a 10-year bond worth $1,000 outstanding, it would still have a 10-year bond worth $1,000 outstanding. But investors would pay more to hold a bond that pays $7 a year than one that pays $3.50, so promising a higher interest rate would allow Treasury to raise more money.

Would those higher interest rates, which would cost the government more money, pose a problem? Not technically. The debt limit applies to the face value of outstanding federal government debt ($1,000 in our example), not future promises to pay interest.

And the idea could also come in a slightly different flavor. The government could issue bonds that pay regular coupons, but which never pay back principal, or perpetual bonds. People would buy them for the long-term cash stream, and they would not add to the principal of debt outstanding.

The premium bond idea has gained support from some big names. The economic commentator Matthew Yglesias brought it up in January, the Bloomberg columnist Matt Levine has written about it, and The New York Times columnist and Nobel-winning economist Paul Krugman made a case for it this week.

But even some proponents of premium bonds acknowledge that it could face legal challenges or damage the United States’ reputation in the eyes of investors. Plus, their design and issuance would have to happen fast.