To amend the Homeland Security Act of 2002 to limit the number of Urban Area Security Initiative grants awarded and to clarify the risk assessment formula to be used when making such grants, and for other purposes.

Amends the Homeland Security Act of 2002 to: (1) limit to 25 the number of Urban Area Security Initiative grants awarded; (2) require the Administrator of the Federal Emergency Management Agency (FEMA), when weighing "threat," "vulnerability," and "consequences from acts of terrorism" in allocating funds, to assign to "threat" a value that is not less than 33%; and (3) apply minimum allocation requirements only to state Homeland Security grants.