The Chief of Army's exercise this week is attempting to peer into the future. This isn't, perhaps, as strange as you might think because the military is desperate to be a "learning environment". After all, the hard edge of battle is death. The enduring question a soldier faces is balancing their mission against that terrible cost.

Our most recent battle was in Afghanistan. It seems reasonable to ask what the enduring achievements of that deployment were. This is a question for the politicians, of course, because the answer depends on what you think our mission was. If the objective was a peaceful, democratic country, we failed. But that's not the only take. For an alternative, nuanced and thoughtful argument try reading The Dust of Uruzgan by diplomat/musician Fred Smith.

Then Prime Minister Tony Abbott in Tarin Kowt, Oruzgan Province, Afghanistan where, in October 2013, he attended a Recognition Ceremony to honour the 40 Australian lives lost during the 12-year conflict. Credit:Andrew Meares

But it's not until page 389 that he reveals the logic in an explosive sentence. Smith correctly emphasises that the moment our boots hit the soft, powdery soil of the Tarin Khot airstrip, "our soldiers achieved the government's first strategic objective … They could have continued to achieve that objective if they had sat on the base playing horseshoes".

This is the crux of any examination of our involvement in Afghanistan: why did we venture outside the wire and what was achieved. Was the deployment worthwhile, despite the death of more than 40 soldiers; the serious wounding of another 260 soldiers and diplomats; and a total cost of well over $7.5 billion?