Without being an armchair politician, all that would happen if we just Nuked the place or whatever would make the country a perfect breeding ground for insurgents. The population who would be turned against us, would be after money to survive, and this would be provided by joining terrorist organizations, and farming opium. Both these things, would increase the threat to ISAF countries.
The idea behind looking after the local population, is that they will choose to be on our side, as opposed to the insurgency. We do this by funding local projects, providing work etc, also by subsidising the cost of grain, so that farmers are less motivated to grow opiates. Progress is unfortunately slow, but there is at least, some progress. Which is far more than can be said for every other unwelcome visitor the country has played host to in the last 150 years.
That said, the people are backwards, and it is a ****hole, so building a huge wall with barbed wire and armed guards around the country might be an idea....
Anyway, anyone seen this:
Land Rover 109 lwb anti mine - armour plated | eBay
I think they had the right idea. Wait for the landy to get blown up, and then roll it back onto it's wheels again and drive away

lol