February 26, 1991:
Saddam Hussein announces the withdraw of Iraqi troops from Kuwait.
February 26, 1993:
Ryder truck bomb attack on WTC in New York City kills 6.
April 19, 1991:
UNSCOM is formed to carry out weapons inspection in Iraq. In this interview with CNN, Tariq Aziz refers to "the end of the war in April 19, 1991".
April 19, 1995:
Ryder truck bomb attack on Murrah Building in Oklahoma City kills 168.
July 17:
Annual celebration of 1969 Ba'athist takeover of Iraq.
July 17, 1990:
Iraqi President Saddam Hussein launches attack on Kuwait and the United Arab Emirates (UAE), charging they had conspired with the United States to depress world oil prices through overproduction. (the official beginning on the "Mother of all Wars" and prelude to the August 2 invasion of Kuwait).
July 17, 1996:
TWA Flight 800 "bombing" (according to George Stephanopoulos) kills 230 passengers.
October 31, 1998:
President Bill Clinton signs H.R. 4655, "The Iraq Liberation Act of 1998", restating the case for Saddam Hussein's ouster and pledging support for the Ba'athist opposition.
October 31, 1999:
Egypt Air flight 990 mysteriously drops into the Atlantic Ocean 30 minutes after takeoff, killing 217. The 767's cockpit voice recorder confirms the co-pilot, Gameel al-Batouti, has complete control when the plane begins to lose altitude. Examination of the flight data-recorder shows that Batouti cut the power and pushed the control yoke forward, sending the 727 into free fall. During the fall, the flight's senior pilot, Captain Ahmad al-Habashi is heard re-entering the cockpit screaming "What's happening? What's happening?". Al-Batouti calmly replies "Tawakkalt ala Allah" ("I rely on God"), and repeats the phrase as many as ten times as the plane crashes into the Atlantic.
June 25, 1993:
U.S. launches cruise missile strikes against Iraqi intelligence for the attempted assassination of President George H.W. Bush in Kuwait City (and, unofficially, for the February WTC attack).
June 25, 1999:
Fuel truck-bomb explodes outside the Khobar Towers in Dhahran, Saudi Arabia killing 19 USAF military personnel and wounding 515 persons, including 240 U.S. personnel.
August 7, 1990:
Operation Desert Shield begins, in response to the August 2 Iraqi invasion of Kuwait.
August 7, 1998:
Two car bombs explode at the American Embassies in Nairobi, Kenya, and Dar es Salaam, Tanzania, killing 224 people and wounding more than 5,000 others.
September 11, 1990:
President George H.W. Bush addresses a joint session of the U.S. Congress on the matter of Saddam Hussein and the looming Gulf War ("This is not, as Saddam Hussein would have it, the United States against Iraq. It is Iraq against the world"). This was President Bush's first major address on the issue.
September 11, 2001:
Terrorists hijack four commercial airliners in coordinated strikes on New York City and Washington, DC, killing over 3000.
P.S. Lack of the USS Cole is interesting. An opportune port call to good to pass up or..?
P.P.S. Are you aware Richard Clarke, while describing a list of terrorist events of the 90's, included TWA-800? Scary.
The best proof of this is their eagerness to destroy Iraq, the strongest neighboring Arab state, and their endeavor to fragment all the states of the region such as Iraq, Saudi Arabia, Egypt, and Sudan into paper statelets and through their disunion and weakness to guarantee Israel's survival and the continuation of the brutal crusade occupation of the Peninsula.
Concerning the date September 11 itself, I think the most likely explanation is that this is the pre-Islamic Egyptian new year celebrated by Egyptian (Coptic) Christians. According to his handler Ramzi Binalshibh, the date was proposed by Atta himself... The modern ideology of jihad, as formulated by Sayyid Qutb (another Egyptian), says that modern Islamic societies have slipped back into "jahiliyah", pre-Islamic ignorance of God, and their rulers are therefore legitimate targets. The Islamists also say that Judaism and Christianity started out in truth but have become corrupted (this is how they can claim Abraham and Jesus as Muslim prophets). The Copts say that September 11 commemorates Christians who were martyred by the pagan Roman emperor Diocletian, but the date does also have a resonance with truly ancient Egyptian culture (the equinoctial flooding of the Nile, the rise and fall of Sirius in the sky). It also appears to be given some prominence in modern, secular-nationalist Egypt (the current Egyptian constitution was adopted on 11 September 1971, less than a year after Sadat took over from Nasser). Finally, it was an Egyptian Copt (Boutros-Boutros Ghali) who was UN Secretary-General at the high point of the post-Gulf War "peace process"... I don't think there's anything very deep here, I think it was opportunistic - Atta had to choose a date, and September 11 fell within range, giving him a chance to send a symbolic message specifically to his countrymen, on top of everything else.