The Cluster bombs and the US wonder

Well over half the world’s governments agreed at the end of May to “consign cluster munitions to the trash bin of history,” in the words of the Cluster Munition Coalition, the civil society collective that delivered the treaty. Meeting in Dublin, Ireland, representatives of 110 governments completed negotiations on a new international treaty that bans the production, use, and export of all existing cluster munitions and commits them to destroy their stockpiles within eight years.
The U.S. government did not attend the negotiations, instead arm-twisting its allies to weaken the treaty. In the end, though, all other major NATO countries joined with the majority in agreeing to get rid of these weapons, which are designed to kill or maim every living thing in an area as large as two football fields. The vast majority of victims of cluster bombs have been civilians.

Stephen Mull, Acting Assistant Secretary for Political-Military Affairs, held a press briefing in the midst of the negotiations to explain why the U.S. government was not at the table. His explanations were creative.

If the convention passes in its current form, any U.S. military ship would be technically not able to get involved in a peacekeeping operation, in providing disaster relief or humanitarian assistance as we're doing right now in the aftermath of the earthquake in China and the typhoon in Burma, and not to mention everything that we did in Southeast Asia after the tsunami in December of 2004. And that's because most U.S. military units have in their inventory these kinds of weapons.
A reporter astutely asked Mull why it wasn’t possible to “just take the munitions off your ships?” Mull responded:

Well, we - the number one priority of any country's military is to defend its country. And if our military planners are determined that these are necessary to protect American interests, we - it's not something that we're going to unilaterally get rid of.
The cluster bomb treaty would be unilateral…except for the other 110 countries that also agreed to abandon cluster bombs in Dublin.

And why are cluster munitions a necessary defense? Mull again had an answer:

These [cluster munitions] are weapons that have a certain military utility and are of use. The United States relies on them as an important part of our own defense strategy.

When the media inexplicably pushed back, asking what, exactly, this military utility was, Mull ruled out some possibilities:

How many wars like that is the United States going to be in, in the foreseeable future. My personal guess is probably not a lot. I don't think we have that kind of threat from Canada or Mexico, by the way, for example.

No doubt the Canadian and Mexican governments are reassured to hear that the United States does not plan to go to war with them anytime soon.