Airforce has offensive lasers in mission pods.
US Army has defensive lasers (more than one) on the Helicopter Fleet.
US Army has medium powered lasers for mortar and rockets defense as well as drones. However it appears Microwave emitters are better for free drone defense.
Lasers can cut the fiber optic cables but, AFAIK & open source, the short dwell time requires high powered lasers which are not fielded. In fact mile long (area not single strand) motorized rotating barbed wire and razor wire do an excellent job of point defense. I imagine non rotating micro razor/tangle anti drone concertina may do the task (sever fiber optic cables) with the least hassle and greatest mobility.