US hypersonic missile defense 'inadequate' due to Fiscal Responsibility Act issues, Pentagon says

A top Pentagon official told Congress that U.S. hypersonic missile defense systems are "inadequate" at least in part due to struggles that the Defense Department is facing due to the Fiscal Responsibility Act of 2023. 

John Hill, the space and missile defense deputy assistant secretary, revealed the concerning vulnerability during an exchange with Senate Strategic Forces Subcommittee Chair Angus King, I-Maine at a hearing Wednesday.

If Russia were to launch a hypersonic missile from the western city of Murmansk, the U.S. would face issues deflecting it, Hill said in response to a question from King.

"The truth is, we have no defense for hypersonic missiles, yes or no?" King asked Hill. "You are the Commander of an aircraft carrier in the Greenland gap. A hypersonic missile launch from Murmansk [travels] 6000 miles per hour. What do you do?"

"We have some systems in the terminal stage, but we need more. You are correct, Sen. King, that our hypersonic defenses are inadequate," Hill responded.

The Fiscal Responsibility Act, passed last year to avoid a government default, places limits on discretionary defense spending. The law, combined with the pressures of inflation, has posed challenges for the Defense Department, Hill also said.

"What we faced in this year and in the budget this year, it was difficult with the Fiscal Responsibility Act we had to work with. We had to pay bills and had to go in on the personnel, salaries, health care, inflation costs," he said. 

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