[latch]

China, Russia India and France have stockpile of supersonic cruise missiles. India is mass producing hypersonic cruise missiles, while Russia and the US are prototyping.

In comparison, most of the cruise missiles we hear about (Tomahawk for example) are subsonic (though the US does have a few old supersonic ones).

The effectiveness of missile defense systems isn't 100%. It's hard to shoot something travelling at 3600mph. It takes a lot of power, a lot of accuracy, generates a ton of heat, and a requires dash (or two) of lady luck. The defensive system can be overwhelmed for a fraction of the price.