This is not a trivial exercise by any means, but feasible enough that enrichment facilities present a significant nuclear proliferation risk.

This case suggests that preventive attacks can increase the long-term proliferation risk posed by the targeted state.

There are no nuclear proliferation risks associated with plutonium-238.

The end result, however, is a consistent and internationally accepted level of proliferation risk.

"They did state that they will take actions to reduce the proliferation risk."

The main controversy surrounds the third category: nations considered "proliferation risks."

Last week, Beijing backed off from its plans to sell nuclear reactors to Iran, a deal that carried serious proliferation risks.

Tehran's secret enrichment activities belie Russian assurances that this nuclear deal will not increase proliferation risks.

A fundamental goal for American and global security is to minimize the proliferation risks associated with the expansion of nuclear power.

"This is a high explosives risk, but not necessarily a proliferation risk," one senior Bush administration official said.