NATO announces formal suspension of Cold War-era security treaty after Russia's pullout

NATO on Tuesday announced the formal suspension of a key Cold War-era security treaty in response to Russia's pullout from the deal. Most of NATO's 31 allies have signed the Treaty of Conventional Armed Forces in Europe, which was aimed at preventing Cold War rivals from massing forces at or near mutual borders. It was signed in November 1990, but not fully ratified until two years later.