This was a voluntary move. They weren't compelled to do it, nor could they ever have been compelled to do it, by the British Army or ten British armies.
But Chairman Mao said " a guerilla must move amongst the people as a fish swims in the sea ". For the IRA, the sea changed noticeably years ago. The people of the six counties were tired of the fighting, the murders, the terror. They wanted a chance to live normal lives.
This disarmament comes after years of discussions inside the six counties, between Ireland and the UK, with a valuable and sustained assist from President Clinton some years back.
An Ireland without IRA military action, and yes, terrorism, is a better place. But lets not parse words here - " Northern Ireland " was built, and maintained, until very recently, on a foundation of prejudice, discrimination, and on varying degrees of state-sponsored terrorism.
When the Catholics marched peacefully, at varying times they were clubbed to the ground, or shot down by heavily armed British paratroopers. The modern IRA was not formed by Gerry Adams or Martin McGuinness, the real architects of the modern IRA are Ian Paisley , and the criminals within the B-Specials, the RUC, the British Army and the Government, who pushed the " nationalists " to the wall time and time again.
You kick a people in the face decade upon decade, and shoot them down in the street when they try to protest, don't be surprised if a few of them pick up the gun against you.
But what's done is done, and what's one is one, and what's lost is lost and gone forever.
I think that the vast majority of the people of Ireland reject terrorism and conflict, and will welcome this move. Let's see how people react. Let the new day begin.