The mortar barrage has left Israeli officials wondering if the new Palestinian leader Mahmoud Abbas can deliver on a cease-fire. “Everything is conditioned on the question, ‘Will the Palestinian leader be able to rein in his terrorist groups?’” said Israeli spokesman Avi Pazner. “This is by no means certain now.” Abbas ordered his security forces to prevent further attacks on Israeli targets and threatened to take unspecified measures if the violence continues. But it appears that Abbas is not strong enough to confront Hamas, and that does not bode well for the truce.