In March 2007, Des Browne was the hawkish Labour defence secretary who pushed the Trident replacement resolution through parliament, in the face of a huge rebellion from his own backbenchers - the biggest since Labour came to power in 1997. Recalling the debates at that time, Browne was adamant that only a submarine-borne ballistic missile system with nuclear warheads - on continuous patrol at sea - could make Britain safe.
This week Des Browne has announced that the thinking which underpinned that decision - and its confirmation by the coalition government in 2010 - needs to be re-examined. In his opinion, important things have changed over the last six years and "it is time for a more honest debate about the defence choices facing the country." Such a change of heart is to be welcomed, not least because - judging by reports of behind the scenes discussions - Des Browne is just the tip of the iceberg. Many people from across the political spectrum are opening their minds to a reconsideration of Britain's strategic and security needs. Unfortunately they are not all as courageous as Browne in speaking out.
And this is not just a one-off statement. He has put considerable effort into the development of the Top Level Group of UK Parliamentarians for Multilateral Nuclear Disarmament and Non-Proliferation, of which he was a founder in 2009. This comprises almost all foreign and defence secretaries from the last two decades, senior military figures and two former NATO secretary generals and is a genuinely all-party body. He is also leading the Trident Commission, an unofficial all-party investigation into Trident, which unlike the Lib Dem Trident Alternatives Review is also considering the non-nuclear option.
Of course there are weaknesses in Des Browne's argument, not least the emphasis on how much things have changed since 2007, apparently seeking to justify his position at that time. In fact, Trident was already illegal, immoral and exceptionally expensive with a significant opportunity cost. He correctly points out that our insistence "that we intend to keep nuclear weapons on permanent deployment for decades while seeking to deny those weapons to everyone else" will threaten the non-proliferation regime. But of course this hypocritical flouting of our obligations under the nuclear Non-Proliferation Treaty has applied for many decades. The end of the Cold War and the emergence of new security threats has also been a factor since well before 2007.
Nevertheless, this intervention is a much-needed reality check for those still backing a full-on Trident replacement. Browne's conclusion is that a like-for-like replacement is plain wrong, and that a lesser option with fewer subs and an end to continuous at-sea patrols is the way to go. That would be a good start. But I am sure I am not the only person who will point out to Des Browne that the logical conclusion of his analysis of Britain's security needs - and the very real threat posed to us by nuclear weapons possession - is actually nuclear disarmament.