(NewsNation) — The U.S. and China have agreed nuclear war should be off the table, but can China’s promises be believed?

President Joe Biden met with Chinese President Xi Jinping at the G-20 summit, and one of the topics of discussion was the possible use of nuclear weapons.

Brent Sadler, senior research fellow of naval warfare and advanced technology with the Heritage Foundation’s Center for National Defense said China’s way of thinking is similar to Russia, with the threat of nuclear weapons being used to try to shift outcomes in their favor.

Sadler said the U.S. is in a strong position to respond, but there are gaps in America’s defense.

“There is one chink in our armor,” Sadler said. “We don’t have adequate tactical nuclear responses.”

The U.S. reduced the number of tactical nuclear weapons in its arsenal after the Cold War. That gives Russia and China several more options to escalate the use of nuclear weapons that the U.S. doesn’t have.

“The only option that we have is to go large and that unravels very rapidly into massive nuclear exchanges and that is something the United States will take a lot of damage and a lot of losses before it makes that decision,” Sadler said.

Watch the full interview in the player above.