Are non Gurkhas allowed to use Kukri Knives in the British army?
Nowadays, the kukri is more about tradition than protection and although Gurkhas may still carry them, they also carry modern weaponry. You would be advised not to take one with you to Afghanistan. For a start you will have to take it on the plane and even if you are flying crab-air, you may still have limits on what you can take on board. They are also quite heavy and you may want to limit how much weight you are carrying on ops. And finally, even though they are nasty beasties, the main threat out there is not from close quarters combat, so it would be of limited use for personal protection. Also, as you say, you are likely to get it confiscated! Get a ceremonial one and treasure it – beautiful silver-work!
