With many Arab nations feeling a rising threat from Israel, the Saudi-Pakistan defense pact announced this week brings Pakistan — and its nuclear umbrella — into the region's security equation.

The "Strategic Mutual Defense Agreement" signed between Pakistan and Saudi Arabia on Wednesday effectively marries Riyadh's money with Pakistan's giant nuclear-armed military, analysts said.

Few details of the pact have been disclosed, and Pakistan's stated nuclear doctrine says that its weapons are solely aimed against long-term adversary India.