Cook resigned from his positions as Lord President of the Council and Leader of the House of Commons on 17 March 2003 in protest against the invasion of Iraq.

In parliament, Cook joined the left-wing Tribune Group of the Parliamentary Labour Party and frequently opposed the policies of the Wilson and Callaghan governments.

He was an early supporter of constitutional and electoral reform (he opposed devolution in the 1979 referendum but came out in favour on election night in 1983) and of efforts to increase the number of female MPs.

[citation needed] During his early years in parliament, Cook championed several liberalising social measures, to mixed effect.

He repeatedly (and unsuccessfully) introduced a private member's bill on divorce reform in Scotland, but succeeded in July 1980 – and after three years' trying – with an amendment to bring the Scottish law on homosexuality into line with that in England.

[citation needed] After Labour were defeated at the general election in May 1979, Cook supported Michael Foot's leadership bid and joined his campaign committee.

[4] Cook became known as a brilliant parliamentary debater, and rose through the party ranks, becoming a frontbench spokesman in 1980, and reaching the Shadow Cabinet in June 1983,[citation needed] as spokesperson on European affairs.

[citation needed] A year later he was made party campaign co-ordinator but in October 1986 Cook was surprisingly voted out of the shadow cabinet.

[citation needed] In 1994, following the death of John Smith, he ruled himself out of contention for the Labour leadership, apparently on the grounds that he was "insufficiently attractive" to be an election winner,[5] although two close family bereavements in the week in which the decision had to be made may have contributed.

Both of these were controversial, the former because it was not sanctioned by the UN Security Council, and the latter because of allegations that the British company Sandline International had supplied arms to supporters of the deposed president in contravention of a United Nations embargo.

Cook was responsible for achieving the agreement between the UK and Iran that ended the Iranian death threat against author Salman Rushdie, allowing both nations to normalize diplomatic relations.

In early 2003, during a television appearance on BBC's debating series Question Time, he was inadvertently referred to as "Robin Cock" by David Dimbleby.

In a statement giving his reasons for resigning, he said, "I can't accept collective responsibility for the decision to commit Britain now to military action in Iraq without international agreement or domestic support."

He also praised Blair's "heroic efforts" in pushing for the so-called second resolution regarding the Iraq disarmament crisis, but lamented "The reality is that Britain is being asked to embark on a war without agreement in any of the international bodies of which we are a leading partner – not NATO, not the European Union and, now, not the Security Council".

After leaving the Government, Cook was a leading analyst of the decision to go to war in Iraq, giving evidence to the Foreign Affairs Select Committee which was later relevant during the Hutton and Butler inquiries.

[25] Chris Smith said in 2005 that in recent years Cook had been setting out a vision of "libertarian, democratic socialism that was beginning to break the sometimes sterile boundaries of 'old' and 'New' Labour labels".

[26] With Blair's popularity waning, Cook campaigned vigorously in the run-up to the 2005 general election to persuade Labour doubters to remain with the party.

Al-Qaeda, literally "the database", was originally the computer file of the thousands of mujahideen who were recruited and trained with help from the CIA to defeat the Russians.

[30][31] Shortly after he became Foreign Secretary, Cook ended his relationship with Margaret, revealing that he was having an extramarital affair with one of his staff, Gaynor Regan.

Between 1991 and 1998 Cook wrote a weekly tipster's column for Glasgow's Herald newspaper,[citation needed] a post in which he was succeeded by Alex Salmond.

At around 2:20 pm on 6 August 2005, while he walked down Ben Stack[35] in Sutherland, Cook suddenly suffered a severe heart attack, collapsed, lost consciousness and fell about 8 feet (2.4 m) down a ridge.

Despite efforts made by the medical team to revive Cook in the helicopter, he was already beyond recovery, and at 4:05 pm, minutes after arrival at the hospital, was pronounced dead.

It is a reference to Cook's strong opposition to the 2003 invasion of Iraq and the words were reportedly chosen by his widow and two sons from his previous marriage.