Wall Street Journalさんのインスタグラム動画 - (Wall Street JournalInstagram)「The weapon Beijing launched over the South China Sea traveled at speeds of more than 15,000 miles an hour as it circled the globe. Flying at least 20 times the speed of sound, it could reach anywhere on earth in less than an hour. ⁠ ⁠ The summer 2021 test flight ended with the missile striking near a target in China, but it sent shock waves through Washington. National security officials concluded Beijing had launched a hypersonic weapon—a projectile capable of traveling at least five times the speed of sound.⁠ ⁠ The weapons can attack with extreme speed, be launched from great distances and evade most air defenses. They can carry conventional explosives or nuclear warheads. China and Russia have them ready to use. The U.S. doesn’t. ⁠ ⁠ For more than 60 years, the U.S. has invested billions of dollars in dozens of programs to develop its own version of the technology. Those efforts have either ended in failure or been canceled before having a chance to succeed. ⁠ ⁠ Washington, having spent recent decades focusing on fights with terrorists and insurgencies, is once again pouring resources into hypersonics. The Pentagon’s 2023 budget includes more than $5 billion for the weapons. The U.S. is also tapping the private sector—including Silicon Valley venture capitalists—to help develop them to a degree rarely attempted in the past.⁠ ⁠ Read more at the link in our bio.」9月22日 9時03分