Counterforce is also a philosophy of nuclear targeting. It refers to the practice of attempting to use strategic nuclear weapons in an attempt to destroy opposing nuclear forces, rather than targets of intrinsic value to the opponent. Doing the latter is called countervalue targeting, and is antonymic to counterforce. Counterforce is inherently destabilizing, because any time an opponent becomes (more) nervous about its own nuclear forces being able to carry out their designated mission (be it counterforce or countervalue) without being destroyed first, there is a motivation to arms race. Resultant methods for dealing with counterforce threats to one's nuclear forces include proliferation (building more weapons), hardening (protecting one's weapons with shielding), and the most destabilizing of all, reducing the requirements for you to launch your own forces. The major step in this last response is to declare a 'launch on warning' policy rather than a 'launch under attack' policy. The problem here is that it's much, much easier to mistakenly decide that one is under imminent nuclear attack (you think the weapons are flying) rather than actual nuclear attack (weapons have detonated). Launch on warning is the ultimate expression of 'use it or lose it' and as such is hideously dangerous since it provides an incentive or indeed pressure to use nuclear forces earlier on in a crisis.