Subsonic cruise missile is is a very easy to intercept. The concept of a slow rocket powered by a nuclear engine is terribly dumb. As these are Putin's wonderful weapons, the US has nothing to fear.
Well if we look at the example of Syria... before they had an IADS then it was actually quite hard to intercept subsonic cruise missiles, but after an IADS was installed it became much easier.
For an area to defend the size of the US however, and a missile with unlimited range that could literally come from any direction... it could circle around Antarctica for a month before heading to the US for example, then it becomes rather harder...
Don't worry Arrow, by the time Burevestnik arrives to US there will be no air defence left, that is the fun with retaliatory weapons like this or Poseidon: you force the enemy to multiply their expenses in defensive coverage (just to avoid being checkmated in strategic field), for no practical benefit at all. Regardless, I don't think there is any nearly solid proof it is subsonic and Russian side has also not interest in clarifying this point to US, so better be cautious about such statements. Shown missile nose seems compatible with supersonic speed and we don't know if the missile has power enough to dash in the last part of an attack.
Subsonic or supersonic, it does not matter... the cost to the US of building an air defence network that covers the entire country would be enormous even if they could do it on the cheap... and they wont... just declaring they have the weapon ready for production costs the US taxpayer tens of trillions of dollars for the next 20 years... that is not going to help with the deficit...
No subsonic speed.
So they say with the first version.... but who is to say the next model doesn't go a little faster but can only do it for 50 years instead of forever...
And the next model is hypersonic, for ten years...
Well, Russia is not thinking about attack but about retaliation. And they would be dead or almost so by the moment they decide to release Burevestnik, so making US pay its offence with complete annihilation it is a relatively easy business.
The US might believe it can attack first and take out most of Russias nuclear capability, and then use its ABM systems to survive any retaliation the Russians might be able to put up... this adds to the retaliation and makes the initial US attack less likely to succeed...
Not trying to defend Arrow but the tass source said its subsonic, its a direct quote
The first prototype of a working example should be subsonic, but over time technology will improve and they will work out ways of improving performance... ie faster at the cost of range or time of operation... they might triple the speed to mach 2.4 or something at the cost of it only being able to operate for 10 years instead of 100 years...
Would be interesting to see what sort of design they come up with... will it eject the warhead over the target and continue to fly and perhaps land the NPP into the local water supply just for good measure?
Such a design could carry quite a few warheads that could be delivered over a period of days or weeks all over the US of A.
They might even adopt an idea of medium altitude flight at transonic speeds so it could fly over vastly greater distances in the time available and spread these extra warheads to unexpected places based on intel about the ultra rich and where their holiday homes are located...