Nuclear Waste on Moon - Troubling Thoughts

The more I've thought about this issue, the less comfortable I've
become with the security aspects of it.

Right now, nuclear materials and worldwide nuclear weapons
development programs are under very strict "active" security and
surveillance.

We're assuming that shooting these waste materials to the moon and
relying on "passive" security, namely distance and supposed
inaccessability, will trump the active measures currently in place.

For a terrorist state to undertake a nuclear development program is
an endeavor fraught with expense, technical difficulty and
frustration, and active measures to derail it. It's a huge
undertaking for a terrorist state.

But, for a terrorist state or organization, if they could mask their
intentions, and instead presented to the world a scientific program
to launch a "lunar material return program" couldn't they get a
robotic device onto the surface of the moon, retrieve unguarded
nuclear waste, launch back to earth and burn up over the country, or
continent of their choice, spreading the plutonium throughout the
atmosphere. Alternatively, survive re-entry, but explosively destroy
the container lower into the atmosphere.

My concerns are that once such a "lunar material retrieval program"
is launched, it will be beyond the control of concerned nations to
stop the dastardly agenda of the terrorist state. What are we going
to do, use the Ballistic Missile Defense Shield to shoot down the
incoming nuclear material?

Of course, if we put in place a robust active security regime on the
moon to store the nuclear material, then this scenario falls apart,
but to just have the material scattered across a crater with no
means to stop a retreival and return mission won't make me sleep
securely at night. I'd rather have the material buried at Yucca
Mountain, with only one heavily guarded entrance into the facility.

Surely, it would be less expensive for a terrorist state to develop
the robotic lander, which could be done secretly, than it would be
to develop a weapon of mass destruction, especially with all of the
world's intelligence agencies watching for signs of such a program,
and key personnel and sensitive technologies being tracked.

The distance and inaccessability of the moon may be a true state of
affiars for now, but I don't think that we can count on that
continuing for long. Then the expense of trying to secure the
scattered nuclear material will fall on the moon colony.

What are your thoughts?