Yes, you can influence events 10km away
The BOFH solution would be to co-locate segments of detonating cord along your fiber path. Combined with some electronic safe/arm devices, slappers, and an occasional booster + main charge to keep things exciting you can defend your cable.
"If I can't have a cable, you can't have that 'effen backhoe blade!!"
Bonus - after a few shots it's unlikely you will have idiots trying to tap the cable, too.