After North Korea test-fired its latest medium-range ballistic missile last month, the Pentagon responded with a bold boast: If the missile had targeted the United States, Japan, South Korea or any other ally, the U.S. would have blasted it out of the sky.

“We maintain abilities to be able to respond quickly and intercept missiles from North Korea if they do pose a threat to us or our allies,” said Navy Capt. Jeff Davis, a Pentagon spokesman.