Republic of Yemen
The formal government of Yemen is the Republic of Yemen, formed, in 1990, from North Yemen (a part of the Ottoman Empire until 1918), and South Yemen (a British protectorate until 1967). North Yemen had existed as the Mutawakkilite Kingdom of Yemen until 1962 and as the Yemen Arab Republic thereafter, with a capital in Sanaa, and South Yemen as the People's Democratic Republic of Yemen, having Aden as its capital. Ali Abdallah Salih, former president of North Yemen, is the current head of state.
While the Republic has an obvious Presidential system with legislative and judicial branches, Yemen has a unique combination of central and tribal government. While Yemen has formal governance mechanisms, the power of tribal leadership cannot be understated. Al-Qaeda has been reported to be focusing on building tribal alliances. 
Government corruption is a severe problem.  Human Rights Watch reported, in December 2009, that the government was dominated by northerners, who suppressed southern interests, , although the political dynamics of Yemen are far more complex than the binary distinction between North and South.
Yemen's head of state is the President of Yemen, who appoints the head of government and Prime Minister of Yemen as well as the vice president. The cabinet is appointed by the president with advice of the prime minister.
Ali Abdallah Salih, the incumbent President, had been president of North Yemen, and became national president when the two Yemens merged. He was reelected for a seven-year term on 20 September 2006, with 77.2% of the vote, and Faysal bin Shamlan receiving 21.8%. Bin Shamlan, who had held posts in the Salih government, died, of a long illness, in 2009. 
Ali Muhammad Mujjawar has been Prime Minister since 31 March 2007.
There is a legislative branch, but it is largely advisory. The bicameral structure consists of a Presidentially-appointed Shura Council of 111 seats and an elected House of Representatives of 301 seats.
A scheduled election was deferred to 2011.
- See also: U.S. policy towards Yemen
There is more than one internal security problem in Yemen, although Al-Qaeda in the Arabian Peninsula (AQAP) gains the most attention. The Yemen Post reports that a major conflict between the U.S. and Yemen is that Washington will not put the Houthi movement on its list of terrorists; it also criticized civilian casualties from a 17 December raid on AQAP. 
As a matter of fundamental policy, Yemen has said it will not allow "foreign troops" on its soil. Yemen has never and will never accept any foreign troops on its territories,' the source said, quoted by the Defence Ministry's weekly newspaper, the 26 September. He said the Arab country 'will continue its unabated open war against the terrorist elements and outlaws and it is capable of pursuing those terrorist elements,' the unnamed source said. The Yemeni source said that 'fighting terrorism is a Yemeni interest in the first instance.'
The source also said Yemen 'will not accept any terrorist on its soil' and that the country 'will not become a safe haven for terrorists.'
The remarks come one week ahead of an international conference on Yemen due to be held in London on January 27.
The U.K. and U.S. Embassies briefly closed, in January 2010, over what was called a specific (but unspecified) security threat; the U.S. Embassy reopened after Yememenite forces conducted a raid that killed two terrorist suspects. 
Mostly in North Yemen, the Houthi movement, named for their leader, Abdul Malik al-Houthi, are of the Shi'a minority. A peace accord signed in July 2008, is tenuous.  Houthis have crossed the border into Saudi Arabia and been attacked by the Saudis; they have asked for help from Iran. 
Abu Yahya al-Libi published a manifesto, entitled "We are not Houthis", distinguishing al-Qaeda from the Houthi movement. Saying that both the Houthis and the Saudi regime are Muslims who have strayed, the document focuses on what he terms the hypocrisy of Saudi Arabia in renouncing the Mujahideen and of the "commandment of Jihad". According to the International Institute for Counter-Terrorism at Herzliya, he said "the Saudi regime and the Wahabbi establishment, succumbing to the former’s dictations, are quick to declare it an obligation to go on Jihad against the Houthis in Yemen, while in other arenas in the Muslim world, such as Iraq, they try to make it more difficult by way of Fatwas forbidding going on Jihad. This fickle policy stems, in his eyes, from certain interests of the House of Saud, such as the relationship with the United States."
Southern secession movement
A secessionist movement in South Yemen, headquartered in Aden, asks the question, according to the Christian Science Monitor, posed by a member of the minority Yemeni Socialist Party, "Eighty percent of Yemen’s oil comes from the south but where does the money go? It goes to Sanaa. The people of the south have not benefited from any of this wealth and now it is running out." Also unnamed, a Northern government member says “The south has all the resources and only one third of the population. We cannot allow them to secede,” said a member of the opposition party Islah in the capital, who spoke on condition of anonymity because he is not authorized to speak for the party. “Northerners will fight to keep Yemen together. They know it is a matter of survival.”
Al-Qaeda in the Arabian Peninsula (AQAP) has attacked targets in the country as well as operating transnationally; a suicide bombing against Korean tourists in March 2009 was one indication of domestic security problems.  The group is a merger between Saudi and Yemenite groups. Its actions had been largely contained to the Arabian Peninsula, but it appears responsible for the attempted suicide bombing of a U.S. aircraft on 25 December 2009.
This is a newer Al-Qaeda "affiliate" than the others, and seems to have learned from their missteps. As opposed, in particular, to operations in Afghanistan, Iraq, Saudi Arabia and Sudan, the group is largely "home-grown" and cooperates much more effectively with existing tribal structures. "They've worked hard to put deep, and what they hope are lasting, roots that will make it very difficult for them to be rooted out of Yemen," says Gregory Johnsen, a Yemen expert at Princeton University. "They've done a good job of looking at the mistakes that other versions of al Qaeda have made elsewhere."
"As long as Qaeda respects the tribes, some tribes will welcome them," says Sheikh Abdulqawi Sherif, the head of the pro-government Bani Dhabian tribe, whose territory borders the al-Qaeda strongholds of Mareb Province and Shebwa Province. Gen. Yahya Saleh, nephew of Yemen's president and the head of one of the country's counterterrorism forces agreed there were alliances, but "the tribes in Yemen are practical. They know there will be a heavy price to pay for harboring al Qaeda, and more and more, [the tribes] will not be willing to pay that price."
Role vs. Republic of Yemen
Yemen's President has offered dialogue with AQAP members, if they "...lay down their arms, renounce terrorism and return to wisdom, we are prepared to deal with them...They are a threat not only to Yemen but also to international peace and security.” 
According to Ali Hasan al-Ahmadi, the governor of the southern Shabwa Province, said: “There are dozens of Saudi and Egyptian al-Qaeda militants who came. This is in addition to Yemenis who came from Mareb and Abyan Provinces and a number of militants from Shabwa itself.” The Times said that intelligence agencies may have been overly focused on Abdul Majid al-Zindani, who is now seen as an older and less influential figure, and had only recently woken up to the danger of the energetic younger Anwar al-Awlaki.
Christopher Bouckek, of the Carnegie Endowment for International Peace, said that AQAP is relatively uninvolved in the popular revolt in Yemen. Barbara Bodine said that AQAP will have more freedom to operate, but both Bodine and Bouckek agreed that Yemen's economy is the major issue driving unrest. 
There will be a 27 January 2010 meeting in London, called by Gordon Brown, about radicalization and the al-Qaeda threat in Yemen. Prime Minister of Yemen Ali Mujawar will represent Yemen in the gathering that will bring together representatives from governments of 21 countries including the G8 nations, the Gulf Cooperation Council, Egypt, Jordan and Turkey, as well as the European Union, United Nations, World Bank and International Monetary Fund, designed to support Yemen, while pushing for economic development and reform. Yemen has stated limits on its sovereignty, but is open to assistance that is compatible with its domestic politics.
- Sarah Phillips, Rodger Shanahan (November 2009), Al-Qa'ida, tribes and instability in Yemen, Lowy Institute for International Policy
- Yemen Corruption Assessment, U.S. Agency for International Development, 25 September 2006
- In the Name of Unity: The Yemeni Government’s Brutal Response to Southern Movement Protests, Human Rights Watch, December 2009
- "Yemen Ex-Presidential Candidate Dies", Yemen Post, 2 January, 2010
- Yemen, Globalsecurity
- Ali Al-Jaradi (28 December 2009), "Stance of U.S. administration on Houthi movement; Houthis and Al Qaeda mixed cards between Washington and Yemen", Yemen Post
- Mohamed Sudam and Mohammed Ghobari (5 January 2010), "Yemen launches major offensive against al Qaeda", Reuters, in Washington Post
- Yemen Economic Update, World Bank, Spring 2009
- Kristen Chick (11 November 2009), "Yemen's Houthi rebels get Iran assurance, ask Saudis to stop strikes", Christian Science Monitor
- Periodical Review, International Institute for Counter-Terrorism, February 2010 – no. 2
- "Why southern Yemen is pushing for secession: With bleak housing blocks and rusty wrecks for taxis, south Yemen residents pushing for secession say they've been sidelined by the government.", Christian Science Monitor, 15 December 2009
- "Qaeda suicide bomber behind Yemen tourist attack", Reuters, 16 March 2009
- Michelle Shephard (2 January 2010), "Yemen: Terror threat? U.S. ally? Nearly failed state?", The Star (Canada)
- Charles Levinson and Margaret Coker (22 January 2010), "Al Qaeda's Deep Tribal Ties Make Yemen a Terror Hub", Wall Street Journal
- James Hyder (11 January 2009), "Yemen offers to strike a deal with al-Qaeda fighters", Times (UK)
- Christopher Boucek, Barbara Bodine (25 April 2011), "Upheaval, Uncertainty in Yemen as Saleh Weighs Exit", PBS Newshour
- "London talks aim to bolster Yemen's al Qaeda fight", Reuters, 26 January 2010
- "Yemen will not allow foreign troops on its soil: official source", Middle East News, 21 January 2010