“Russia has an incredibly powerful military.

It is important to understand how they have transformed their military over the past 20 years.

I think it is also important to realize that this event did not happen overnight, ”he said during a speech to the Atlantic Council of the nongovernmental organization.

Hayten noted that a serious challenge for Washington is interaction with Russia and China - two countries with nuclear weapons.

"This is a huge challenge ... It is extremely important that we effectively deal with Russia and China at the same time," added the military leader.

In July, Pentagon spokesman John Kirby said the US viewed Russia's development of hypersonic weapons as a threat.