美国有线新闻 CNN 俄罗斯高超音速导弹发射成功 美国防部长称俄新武器不影响美战略（在线收听）

And our first story concerns a weapon that said to be hypersonic, meaning it would travel at several times the speed of sound. Russia's defense ministry says it's conducted a successful test of a hypersonic missile. A nation might want to want a weapon like that because in theory, it would fly fast enough to get through missile defense systems, which are designed to shoot down incoming projectiles.

Russia says its hypersonic missile was launched from a fighter jet that it's intended to hit targets on land and at sea and that the one it tested hit a specific spot at a training ground. Russian President Vladimir Putin called the missile invincible and says his country has the greatest nuclear potential in the world.

But there is some skepticism about whether Russia really has a working hypersonic missile. A U.S. government official says there's doubt that the weapon President Putin described was even close to being operational. And that was echoed by U.S. Defense Secretary James Mattis.

JAMES MATTIS, DEFENSE SECRETARY: And I would just tell you that I saw no change to the Russia military capability and each of these systems he's talking about that are still years away, I do not see them changing the military balance. They do not impact any need on our side for a change in our deterrent posture.

AZUZ: International analysts say President Putin might be promoting his country's military strength in order to portray himself as a strong leader in Russia and abroad. Russia has a presidential election scheduled for March 18.