Helicopter losses

There hasn't seemed to have been many obvious connections between what the British Army learned in its three-decade long counter-insurgency campaign in Northern Ireland and the situation in Iraq, but I do remember some years ago reading that what the British military feared most was the IRA getting ground to air missiles. In the rural areas near the border with Ireland, known as 'bandit country', land transport was never safe even for military forces, let alone the police, so the UK relied greatly on helicopters for resupplying border observation posts, to ferry troops around and the like. As far as I remember no British helicopter was ever shot down. The Soviets started losing in Afghanistan when the mujahideen began to be able to bring down their helicopter gunships as well, and it was tactics that were developed in Afghanistan that were used by the Somalia fighters who brought down the US Blackhawks in Mogadishu in 1993. So the news that the US has lost another helicopter to ground fire is very worrying, suggesting that insurgents are getting - and being able to deploy - heavier weapons and whilst the fighting gets worse - particularly in the light of yesterdays horrendous truck-bombing - it is going to be harder for the US forces to be able to move around to try and stop that violence.