This of course depends on the period of Cold War we're talking about. David Miller's book The Cold War: A Military History explains that from 1974, the French strategy was to use its short-range tactical PLUTON and HADES missile systems to fire a "final warning" in order to show French commitment to escalation. These systems didn't have range much beyond East Germany at best, a fact that was pointed out and apparently resented by the Germans; it seems that had the balloon gone up, the French might just have been willing to incinerate some Germans (East or West) to make their point to the Soviets. Of course, both PLUTON and HADES were tactical systems, meaning they'd be used against military targets such as logistic sites, bridges, or troop concentrations, not against cities.

Had these warning shots failed and had the French heartland been attacked, the French "Force de dissuasion" would have executed its retaliatory mission against cities and industrial targets. In 1974, the core of this mission would have consisted of up to 64 Mirage IV nuclear bombers with AN-11 or -22 gravity bombs; although these were supported by KC-135 tankers, it seems likely at least some missions could not expect to recover to friendly airbases. From 1971, the French had in their arsenal intermediate range ground and sub-launched ballistic missiles as well; these could put at least Moscow at risk. In the 1980s, the AN-22s were replaced with air-launched ASMP nuclear tipped missiles, giving the Mirage IVs some stand-off capability.

The French adopted a countervalue strategy, meaning they would have concentrated on incinerating Soviet people and industrial infrastructure as a retaliation. In addition, tactical nuclear weapons were available to ground forces as well. The countervalue doctrine was apparently so well entrenched that there were arguments against upgrading missile systems to more accurate ones, since more accurate missiles might be used for counterforce attacks (against enemy nuclear weapons), thus "diluting" the deterrent value.