The IRA has destroyed all its weapons

"The IRA has destroyed all its weapons and publicly committed itself to peace but for Unionists that's not good enough. To them the very existence of an IRA leadership is a threat."

That sums up the BBC's attitude to Northern Ireland; if the IRA say something it is true and the Unionists are the ones blocking peace and the inevitable move to a united Ireland. How does the BBC's Ireland correspondent, Mark Simpson, know that the IRA has destroyed all of its weapons?