Yemen's stability had always depended on its president. That Ali Abdullah Saleh's removal from politics may have been because of a rocket attack - rather than a negotiated settlement - only complicates the picture.
It is too soon to declare Mr Saleh's political demise, with many of his family members still in positions of power. But certainly the injuries he sustained in Friday's mosque attack and his evacuation for medical treatment in Saudi Arabia have opened a window for change. The president had long been the focus of protests; his opponents have to see that ending the violence would be the most telling victory against him.
Opposition parties calling for Mr Saleh's removal have welcomed a political transition and insist that he will not be allowed to return. If the president had managed a more deliberate exit, a now-shelved GCC plan would have seen power handed to a transitional council. Immediate foreign mediation, led by the GCC and the United States, could still restart that diplomatic process.
The question is who should be involved. Mr Saleh's argument that his departure would result in a political vacuum, although ultimately unconvincing, was his best remaining claim to office. His powers ostensibly have been transferred to the vice president, Abd Rabbu Mansour Hadi, but the extent of Mr Hadi's real authority is unclear. Tribal disputes in the capital, Islamist militants in the south and youth-led protests throughout the country are tearing at Yemen's stability, which is fragile in the best of times.
The worst-case scenario would be if the urban battles that have killed more than 160 people in the last two weeks spiral out of control. In the capital, the fiercest fighting has occurred since high-level figures began turning against the president, including Sheikh Sadiq al Ahmar, the chief of the Hashid tribal confederation, and General Ali Moshen, formerly a Saleh loyalist, who joined the protests in March.
Any diplomatic initiative will have to reach out to many players with competing interests. In no small part, Mr Saleh's personality fed the rivalries that have been tearing the country apart, but Yemen has no shortage of systemic problems. The reforms that protesters originally demanded - and to which Mr Saleh initially agreed - would have been the start of a solution. It is up to his many opponents to prove that they are more credible leaders.
