Nobody is sure if they'll work or not. Since the nukes during the Great Ghost Dance didn't work, then Sam Verner's own Ghost Dance deactivated some, finally the nuclear incident in Chicago; it's not a reliable weapon.
2004 : Israel retaliated to a chemical attack by nuking half of Libyan cities. It worked (
Rulebook,
Target: Wastelands).
2006 : North Korea launched one missile at Japan. It didn't work (
Rulebook).
2009 : SAIM commando had the Lone Eagle of fame launched at Russia. It didn't work (
Rulebook).
2030 : India and Pakistan fires nukes in Kashmir. It worked (
Shadows of Asia).
2056 : Ares brings a tactical nuke to Chicago. It worked (well, more or less,
Burning Bright,
Bug City).
France conducts regular underground nuclear testing off the coast of French Guiana (
SOTA:2064).
2064 : Winternight has magically modified nuke exploding all over the world (
System Failure).
So (1) nukes have been working more often than not (2) the two well-known failures happened
before the Awakening.