The boy who cried wolf: Should Putin's nuclear threat be believed?

Vladimir Putin's decision to forward deploy tactical nuclear weapons to Belarus has made headlines around the world - but forward-basing of nuclear weapons has limited military benefit.

Intercontinental ballistic missiles have virtually unlimited range, so forward-deploying nuclear weapons to Belarus territory is not driven by military necessity.

However, the primary benefit is maintaining the omnipresent threat of nuclear confrontation at the forefront of Western leaders' minds, to deter continued western military support for Ukraine.

So, this appears to be further sabre-rattling by Putin - but at what cost?