Soon after the sectarian Kingsmill massacre occurred, when ten Protestant men returning home from their work were ordered out of a minibus they were travelling in, and executed en masse with a machine gun on 5 January 1976.

[17][20] The capture of Keenan was a blow to the IRA, in particular as he was carrying an address book listing his contacts including Palestinian activists in the United Kingdom.

[20] Keenan stood trial at the Old Bailey in London in June 1980 defended by Michael Mansfield, and was accused of organising the IRA's bombings in England and being implicated in the deaths of eight people including Ross McWhirter and Gordon Hamilton-Fairley.

To those of us who have struggled for years in a purely military capacity, it must be obvious that if we do not provide honest, recognisable political leadership on the ground, we will lose that war for peace.

Following the events after the IRA's ceasefire of August 1994 he had been openly critical of Gerry Adams and the "tactical use of armed struggle", or TUAS, strategy employed by the republican movement.

[25] In November 1998 Keenan addressed a republican rally in Cullyhanna, County Armagh to mark the 25th anniversary of the death of IRA member Michael McVerry.

[26]Keenan continued by saying that if republican demands were not met then British Prime Minister Tony Blair would be responsible for the consequences,[26] and went on to say: So in the future maybe the jails are going to be full again...If our enemies don't want peace, there can only be one conclusion: they must want war.

[5][27] Keenan confirmed his continued commitment to the Armalite and ballot box strategy, saying that both political negotiations and violence were "legitimate forms of revolution" and that both "have to be prosecuted to the utmost".

[27] Keenan played a key role in the peace process, acting as the IRA's go-between with the Independent International Commission on Decommissioning.

[5][28] Keenan resigned from his position on the Army Council in 2005 due to ill-health, and was replaced by Bernard Fox, who had taken part in the 1981 Irish hunger strike.

[30] It is alleged by the Irish Independent and The Daily Telegraph that Keenan succeeded Thomas "Slab" Murphy as Chief of Staff of the Provisional IRA at some point between the late 1990s and the mid-2000s before he relinquished the role to deal with his poor health caused by cancer.