In April 2004, Tatchell joined the Green Party of England and Wales and in 2007 was selected as prospective Parliamentary candidate in the constituency of Oxford East,[3][4][5] but in December 2009 he stood down due to brain damage acquired mainly during protests, as well as from a bus accident.

The Victoria state government and Melbourne city council attempted to suppress the anti-Vietnam War campaign by banning street leafleting and taking police action against anti-war demonstrations.

On graduating he became a freelance journalist specialising in foreign stories, during which he publicised the Indonesian annexation of West Papua and child labour on British-owned tea farms in Malawi.

[46]: 99–109 In the book, Tatchell also argued for a British withdrawal from NATO and for the establishment of a European Self-Defence Organisation, independent of both the United States, as he felt that Europe had become too dependent on their military protection,[46]: 55–59  and the Soviet Union, which he condemned for their invasions of Czechoslovakia and of Afghanistan, as well its internal repression.

[47] In February 2000, Tatchell resigned from Labour, citing the treatment of Ken Livingstone during the nomination of a candidate for Mayor of London, and of similar cases in the Scottish and Welsh elections, as evidence that the party "no longer has any mechanism for democratic involvement and transformation".

[55] He advocated military and financial aid to opponents of the Saddam government, suggesting that anti-Saddam organisations be given "tanks, helicopter gun-ships, fighter planes, heavy artillery and anti-tank and anti-aircraft missiles".

In 2003, Tatchell said he supported giving "massive material aid" to Iraqi opposition groups, including the "Shi'ite Supreme Council for Islamic Revolution in Iraq" (SCIRI), to bring down Saddam.

[63] In December 2016, Tatchell and others disrupted Corbyn's speech on human rights on the basis that the Labour leader had responded insufficiently to the bombing of Aleppo and urged him to condemn Russian military intervention in Syria.

[66] On 13 February 2016, Fran Cowling, the national LGBT representative for the NUS, refused to share a platform with Tatchell at Canterbury Christ Church University to discuss the topic of "re-radicalising queers".

[68] Tatchell responded that no evidence could be produced to support either claim, and that Cowling had never consulted the NUS membership before deciding to make pronouncements on their behalf, and said, "This sorry, sad saga is symptomatic of the decline of free and open debate on some university campuses.

The MP Sir James Kilfedder, an opponent of gay equality who received one of the letters,[75][76] died two months later of a sudden heart attack—on the day one of the Belfast newspapers planned to out him.

Rabbi Dame Julia Neuberger, who had campaigned for gay rights, said, "Drawing a comparison between Lord Jakobovits and Himmler is offensive, racist and [...] makes OutRage appear antisemitic".

The campaign has had positive effects, with seven of eight original murder music singers signing the Reggae Compassion Act, which says that signatories will not "make statements or perform songs" that incite hatred or violence.

He stated that he wished to exempt these people from being "treated as criminals by the law", and that there should be no prosecution if the difference in ages of the sexual partners was no more than three years, provided that these youths were consenting and were given a more comprehensive sex education at a younger date.

[118][119] Tatchell is a critic of Iran's criminal code, which has parts based on sharia and which prescribes punishments for zina offenses, including consensual sexual relations between same-sex partners.

opposed a boycott of WorldPride Jerusalem because holding the event would be a "huge defeat for the Christian, Judaist and Muslim fundamentalists who want it banned and who believe lesbian and gay people should be jailed, flogged or executed".

The attempt of Mr Tatchell to focus attention on the role of the grand Mufti in Moscow, in the face of numerous attacks on gay rights in Eastern Europe, which overwhelmingly come from right-wing Christian and secular currents, is a clear example of an Islamophobic campaign.

[142][143][144] In an essay for the book Sex and Politics in South Africa, he describes how his lobbying of the ANC and Thabo Mbeki in 1987 contributed to it renouncing homophobia and making its first public commitment to gay and lesbian human rights.

[147] In 2002, he brought an unsuccessful legal action in Bow Street Magistrate's Court for the arrest of the former U.S. Secretary of State, Henry Kissinger, on charges of war crimes in Vietnam and Cambodia.

[148] Part of Tatchell's political activism and journalism in the 1970s involved the Rhodesian Bush War, in which he supported the black nationalist movement, including the Zimbabwe African National Union and its military wing.

[160] This speculation proved to be unfounded; the Mugabe regime initially dismissed the ZFM as a hoax before claiming it was an effort orchestrated by the opposition Movement for Democratic Change (MDC) party.

[166] For over 20 years, Tatchell has written and campaigned about environmental problems including global warming and resource depletion, pointing out that they often have a disproportionately negative impact on developing countries.

[167] In August 2008 Tatchell wrote about speculative theories concerning possible atmospheric oxygen depletion compared to prehistoric levels, and called for further investigation to test such claims and, if proven, their long-term consequences.

[181] On 15 September 2010, Tatchell, along with 54 other public figures, signed an open letter, published in The Guardian, stating their opposition to Pope Benedict XVI's visit to the United Kingdom.

Two of his highest-profile campaigns involved Muslim victims—Mohamed S, who was framed by men who first tried to kill him and then jailed him for eight years, and Sid Saeed, who brought a racism and homophobic harassment case against Deutsche Bank.

"[203] In the book "Out of Place: Interrogating Silences in Queerness/Raciality", in a chapter called "Gay Imperialism: Gender and Sexuality Discourse in the 'War on Terror'", Jin Haritaworn, Tamsila Tauqir and Esra Erdem wrote, "rather than help, politics such as Tatchell's have worsened the situation for the majority of queer Muslims.

[206] In October 2004, 2,500 Muslim academics from 23 countries condemned Qaradawi, and accused him of giving "Islam a bad name and foster[ing] hatred among civilizations" and "providing a religious cover for terrorism".

[207] Tatchell argued that Qaradawi expresses liberal positions to deceive the Western press and politicians, while being "rightwing, misogynist, anti-semitic and homophobic",[208] using his books and fatwas to advocate female genital mutilation, blame for rape victims who dress immodestly, and the execution of apostates, homosexuals, and women who have sex outside marriage.

[216]In 1987 Tatchell appeared on the second programme of the first series of After Dark, a discussion on press ethics with, among others, Tony Blackburn, Victoria Gillick, Johnny Edgecombe and a Private Eye journalist.

On Malcolm X's birthday in 2005, Tatchell endorsed Bruce Perry's biography of the African American activist in an article calling for black gay role models, outlining the book's reports of X's same-sex relationships and sex work.