I just want to note the distinction between a UN Security Council embargo and the ATT, because I think there is a fundamental distinction. One is the action of the Security Council that is then binding on all UN member states, so in a sense it's a collective process settled by the Security Council, but it then becomes a requirement of all states. The ATT will require each national government to interpret the treaty in making its decisions about national transfers, and the states will be held to account for those decisions. So it will depend, I think, on how egregious the situation may be to determine how other states react to national decisions about transfers.
On June 11th, 2012. See this statement in context.