Possible Clues:

• Examine graduate on new agreement on weapons
• Threat ultimately absent possibly on account of this?
• Battens down (28s, etc?) with this agreement
• 'No nukes' agreement
• Nuclear cease-fire
• 1996 United Nations treaty subject (2 words)
• Antinuke pact topic
• Mutual agreement to stop exploding nuclear weapons
• Leaving Cert History, for instance, on Prohibition and outcome of The Treaty before it went nuclear?
• Important treaty topic (2 words)