He's deputy leader of al-Qaida in the Arabian Peninsula. He hates the Saudi monarchy and wants to bring it down -- and he's determined to hit the United States with a Sept. 11-scale attack.
"AQAP clearly has the capability and intent to conduct, support and inspire innovative attacks against the American homeland," Texas-based global security consultancy Stratfor reported in an Aug. 26 analysis.
AQAP, which emerged in 2009 after Saudi and Yemeni jihadists joined forces under one banner, has become one of the key operational al-Qaida nodes. It clearly has transnational ambitions that go far beyond toppling the House of al-Saud in Riyadh, although that is one of al-Shihri's main objectives.
Al-Shihri, the son of a Saudi army officer, joined al-Qaida in Afghanistan in 2000. He was wounded in a U.S. airstrike and captured in Afghanistan after Sept. 11, 2001. He was sent to Guantanamo Bay in January 2002. As Prisoner 372, he was released in November 2007. He returned to Saudi Arabia for rehabilitation but later fled to Yemen to rejoin the jihad.
AQAP's leader is Nasser al-Wahayshi, a Yemeni. But it is al-Shihri who has emerged as the operational commander. A diehard jihadist, he is a dynamic, innovative leader who has been behind just about all of the group's major strikes over the last two years.
"The influence that al-Shihri has had on AQAP, apart from being the second man organizationally, seems to be significant on two levels," says Murad Batal al-Shishani of the Jamestown Foundation, a Washington think tank that monitors global terrorism.
"He is responsible for the funding channels of AQAP and for defining the organization's offensive strategy. …
"The fact that Yemen has recently gained notoriety as one of the most crucial areas where al-Qaida is freely operating and aiming to create a safe haven can be largely credited to Said al-Shihri," al-Shishani wrote in a recent assessment.
"In less than one year, AQAP was able to prepare attacks outside of Yemen's borders either regionally or internationally."
These included the attempted assassination of a senior Saudi leader, Prince Mohammed bin Nayef, on Aug. 27, 2009, in his palace in the Red Sea city of Jeddah and the abortive bid by a Nigerian would-be suicide bomber to blow up a Northwest Airlines flight over Detroit on Christmas Day 2009.
Both of those attacks failed, but they demonstrated al-Shihri's meticulous, highly original and dangerous planning skills.
In the attack on Prince Mohammed, son of Saudi Arabia's powerful interior minister, Prince Nayef, and the security chief who crushed al-Qaida's 2003-06 offensive in the kingdom, al-Shihri came up with a novel form of suicide bombing: underpants soaked in liquid explosives that get past security searches and body scanners.
One of al-Shihri's men, Abdullah al-Assiri, posed as a repentant jihadist who wanted to surrender to Prince Mohammed. He was flown from Yemen to Jeddah aboard the prince's private jet and taken to an audience in the palace.
The plan was for al-Assiri to blow himself up when he was standing next to the prince, but something went wrong and the explosives detonated when he was a few feet from the royal.
Prince Mohammed suffered only minor wounds, but the attack was the first against a member of the Saudi monarchy by al-Qaida. It was a clear signal from al-Shihri that the Saudi royals were firmly in his crosshairs.
In a 17-minute audiotape released June 3, al-Shihri called on supporters to kidnap members of the Saudi royal family to secure the release of imprisoned jihadists.
The Christmas Day bombing attempt by a young British-educated Nigerian was just as cunning. Umar Farouk Abdulmutallab, the son of one of Nigeria's leading bankers, was chosen by al-Shihri because he did not fit any terrorist profile and could get through security checks.
Abdulmutallab also wore underpants impregnated with explosives, powerful enough to blow a hole in the airliner's fuselage as it flew over Detroit and send it crashing into the city. But he was allegedly unable to activate the detonator and set himself on fire instead.