Yemen's Ali Abdullah Saleh has interfered with every single move towards the country's reform. The result has been a paralysed government and parliament, leaving the new guard essentially powerless.
Saleh's death grip pulls Yemen's army into enemy camps
The showdown between Yemen's new president and its old air force chief has created a dramatic challenge to the country's stability. Earlier this month, President Abdrabu Mansur Hadi sacked air force commander Brigadier General Mohammed Saleh Al Ahmer, who is the half-brother of former president Ali Abdullah Saleh.
When Gen Al Ahmer refused to leave, troops and tribesmen loyal to him seized Sanaa's airport. They withdrew after a day but Gen Al Ahmer still refuses to cede his position to Mr Hadi's man, Rashid Al Janad.
This is more than a struggle for a single military office. Gen Al Ahmer has tacit or explicit backing from many relatives and supporters of Mr Saleh who are still in prominent positions. Mr Hadi's power and stature are on the line in this face-off, which was part of a wide-ranging personnel shuffle intended to put the new president's mark on the government.
Ten days after the crisis began, Mr Hadi, who is supposed to be supreme commander of the armed forces, gave Gen Al Ahmer 48 hours to hand over power, warning that the alternative would be loss of rank and a military trial. There was no response from the general, who is said to have been urged by Mr Saleh to stand his ground.
The incident seems to be the first real test of Mr Hadi's ability to control the country and to use his presidential powers - and the outcome is still undetermined. The April 6 shuffle also included the dismissal of two other Saleh family members from important army posts, spurring a broad stand-off between Mr Hadi and Mr Saleh.
Negotiations between the two have reached a dead end, with each trying to prove that he is the stronger. Mr Hadi even rejected a request to receive Mr Saleh in his office.
In this struggle, the usually silent battle among Yemen's factions is flaring up dramatically, with potentially disastrous consequences. Mr Saleh's supporters are facing not only the pro-democracy movement that has demanded his departure for years, but also Mr Hadi, the defence minister Mohammed Nasser Ahmed, and many others.
But Mr Saleh is still supported by 24 army brigades, including the Republican Guard commanded by his son Ahmed Ali Saleh, in addition to the central security forces led by his nephew Yahya Saleh and the elite National Security intelligence agency led by another nephew, Ammar Saleh.
The faction led by Mr Hadi is supported by 23 army brigades including the first armoured division commanded by Gen Ali Mohsen Al Ahmar, who split with Mr Saleh's regime last year.
Mr Saleh's military support appears to include about 60 per cent of the army, including those with the best, most modern weapons. These units are loyal to the Saleh family, not to the state. Many lower-level commanders have been bribed to keep this loyalty strong.
The other part of the army, supported by the pro-democracy movement and under the leadership of Gen Mohsen, seems to be weak in term of weapons and training but may well be stronger in its morale, which is based on religion and on nationalist ideology.
Patching the divided army back together will obviously not be easy. Another complication is that many commanders and soldiers are also loyal to their own leaders in the Hashed, Bakil or other tribes, and also to religious and political figures.
Under local and international pressure, Mr Saleh agreed to step down through a presidential election process in February. But he is plainly not yet ready to give up power. Mr Hadi and the transitional government have power in theory, but Mr Saleh is still the dominant political force, using his influence throughout the country to rule Yemen through the security forces.
By remaining in Yemen, Mr Saleh has not only blocked the army restructuring, but has interfered with every single move towards reform. The result has been a paralysed government and parliament, leaving Mr Hadi essentially powerless.
Mr Saleh may be trying to buy time to further weaken Mr Hadi and the new government. Stalling the army reshuffle means he can keep his family members in top security positions, while Mr Hadi must deal with other problems, including terrorist groups in Abyan province and tribal conflicts in Mareb province.
If, as some predict, Mr Saleh agrees to a conditional, limited army restructuring, he will be able to create trouble for the new commanders, and he could use loyalist units to punish his opponents. Further instability serves his purposes, demonstrating that his regime provided more security than its successor.
Mr Hadi's goal was to finish the army reorganisation before the National Dialogue Conference scheduled for late May, but it is still not clear how he will accomplish that, or if he will be able to integrate his hard-line opponents. Even if Mr Hadi tries to impose his will by force, he will need longer than expected, and there is little guarantee that he can succeed.
Khaled Al Hammadi is the president of Freedom Foundation - Yemen and the winner of the International Press Freedom Award 2011 from the Canadian Journalists for Free Expression
On Twitter: KhaledHammadi