>>509649591
>what weapon or device will be a definitive counter to drones?
Right now, other drones are the best counter to drones.
It sounds stupid, but they can track them with radars, get up close and disable them either with an onboard miniature gun or a net before they’re able to inflict human casualty.

Directed energy weapons are largely obsolete. However, a very strong laser like this could essentially burn the drone right out of the sky: https://youtube.com/watch?v=UBVlL0FNbSE

In short:
A combination of ground based portable lasers and drones that take them out is the best current defence.

In future, we might develop an EMP type device but this is still a while away.