Traditional arms control initiatives involved negotiating treaties between states. A series of recent terrorist attacks, most notably the September 11, 2001 attacks against the USA, have brought into sharper focus the reality of terrorist groups' ability to act. They have demonstrated the intent and capacity to do so and are constantly seeking new instruments to carry out attacks. The international community is increasingly preoccupied with the potential dangers of WMD falling into the hands of non-state actors.
It is therefore crucial to deter the people who help to develop WMD from proliferating weapons, material and know-how. Buyers and suppliers play critical parts in any weapons development program, as do the scientists, engineers and technicians who piece together weapons.
Intelligence, military and law enforcement services are cooperating to identify people involved in illicit WMD activities. When they find them, UN Security Council Resolution 1540 obliges states to ensure that proliferation-related activities are treated as criminal, and that proliferators are punished.
Cooperative threat-reduction projects in the former Soviet Union (e.g. Nunn-Lugar Amendment; G8 Global Partnership) gainfully employ former WMD experts, to reduce chances of their knowledge being sold to the highest bidder.