The following is a condensed and edited version of testimony that Air Force Gen. John Hyten, the U.S. strategic commander in charge of America’s nuclear forces, gave the Senate Armed Services Committee last Tuesday. The questions asked by senators have been paraphrased while Hyten’s answers are verbatim, edited only for clarity and length.

Q: Can you explain the threat from hypersonic glide weapons, which can change course midflight and are currently under development by Russia and China?