Disarmament treaties are largely a product of the Cold War arms build up. Recognizing that the nuclear stockpiles held by the Soviet Union and the United States were far greater than what it would take to obliterate life on the planet, let alone fight a war, attempts were made to reduce these armaments.
This disarmament would have to occur bilaterally and verifiably for it be effective (at reducing the threat of a nuclear holocaust). Both of these concerns lead to grave difficulties with such treaties.
There have never been any similar treaties involving conventional weapons, although one might consider a barroom armed standoff to be an instance where one would be a good idea - "you put down your gun while I put mine down - slowly, now - and we'll let cooler heads prevail". Such a situation might reduce injuries to bystanders (we can safely assume the people who pulled the guns don't mind getting shot).
Korean Airlines Flight 007 for the consequences of violation over Kamchatka of U.S.-Soviet Union Salt II agreements