The brave men and women who defend this nation know they cannot do their job without being in harm’s way. It is what they are trained and equipped for. But nothing can truly prepare family and friends for the loss of a loved one.
Every death, every injury, reminds us of the human cost to service in the Armed Forces. The shocking loss of British lives this week - the worst for many years - understandably raises questions about the continued presence of UK forces in Afghanistan; about why we are there and what we are achieving.
I am clear about the answers to those questions: the mission is necessary for national security. UK forces, and troops from 49 other nations, are preventing Afghanistan again being used by Al-Qaeda and other terrorists as a base to plan attacks against the UK and our allies. We are fighting there to prevent them attacking us here.
Of course, addressing the terrorist threat in Afghanistan is not the whole solution, any more than the killing of Osama bin Laden in Pakistan has extinguished Al-Qaeda. But we have got to make sure that Afghanistan is secure and that the terrorists who thrive in chaos cannot re-establish their pre-9/11 training camps.
The reinvigoration of campaign strategy in the last few years is achieving our aims - building the capability of the Afghan Government to maintain its own security, and by extension protect ours.
We’re not there to impose a western liberal democracy in Afghanistan, but an enduring solution in Afghanistan that meets the needs of UK national security and must encompass all its different peoples. Security must be linked with progress on development and governance, and, crucially, with a sustainable political settlement. But, to be successful, the Afghan Government must be able to negotiate from a position of strength.
Building up the strength of the Afghan National Security Forces [ANSF] is a central part of this. We are training them, mentoring them, operating alongside them, and then steadily drawing back as their capability improves. As they step up, we can step back.
This strategy is demonstrably working. The ANSF are now over 320,000-strong and well on course to meet their full strength targets. There remain specific challenges, but the capability and quality of ANSF personnel is improving all the time. This has enabled the Afghans to take lead responsibility for security provision for about half of the population of Afghanistan.
The Afghan Government is preparing to announce the next tranche of transition, demonstrating both the success of the process and their commitment to taking responsibility for their own security.
Central Helmand, where the majority of British troops operate, is a particular success story. Despite the terrible events of this week, the overall trend of successful attacks and UK casualty numbers are sharply down.
By mid-2013, the Afghans are expected to be leading security provision across the whole of the country, with ISAF in support. By the end of 2014 British troops will be able to end their combat role completely. British troops will remain to train the ANSF, but in much fewer numbers. And we will help to finance the Afghan forces as part of the international effort.
The insurgency remains a nationwide threat, capable of undermining progress, and parts of Helmand itself remain dangerous and sometimes deadly as this week’s events have shown. So I understand it when people question our continued presence in Afghanistan and want the sacrifice being made by our Armed Forces to come to an end immediately.
But our national security requires us to see the job through and we owe it to the all-too-many who have sacrificed their lives to see this mission successfully concluded. This is a volatile region from which threats to Britain and our allies may continue to emerge.
Walking away is not an option. I know that our nation will continue to stand by our Armed Forces and the sacrifices they and their families make.