A shared deterrence?

The author discusses what can be shared regarding deterrence: what is it about, and does it deal with the usage decision, with the nuclear budget, with deterrence means, with associated risk and responsibilities? He recalls some aspects of the French military nuclear programme, and outlines that the French nuclear deterrence has a European dimension which has been emerging in time, and thus plays the role of a nuclear umbrella even it does not have the nuclear power of the USA but could however entail damages which could be unbearable for Russia or China. Then, the author addresses the issues of usage decision, of the sharing of the budgetary burden, of the deterrence means, and of risks and responsibilities