Saudi Arabia and nuclear-armed Pakistan signed a formal mutual defense pact on Wednesday, in a move that significantly strengthens a decades-long security partnership amid heightened regional tensions. The enhanced defence ties come as Gulf Arab states grow increasingly wary about the reliability of the United States as their longstanding security guarantor. Israel's attack on Qatar last week heightened those concerns. "This agreement is a culmination of years of discussions. This is not a response to specific countries or specific events but an institutionalization of longstanding and deep cooperation between our two countries," a senior Saudi official told Reuters when asked about its timing. Israel's attempt to kill the political leaders of Hamas with airstrikes on Doha, while they were discussing...