You're a 'military professional' and you come out with this?
1. The complete border cannot be fenced due to the riverine terrain. You cannot mine river beds as they become flooded during monsoons rendering the mines useless. You cannot keep laying thousands of mines every year. You haven't been to the area have you? If you had, you would have understood.
2. They were. Have you tried sniffing an area 26 km in circumference. Do some maths to find out the sq km to be searched/sniffed.
3. Are you aware that thermal imagers and NV goggles are useless in built-up areas like the air base within and outside, having schools, hospitals shopping centers and other buildings? If you didn't know, thermal imagers/NV devices can't see through walls. Further, your ignorance of the area makes you spew rubbish because TIs cant see through thick sarkanda grass 6 - 8 ft high covering thousands of meters in length and breath on both sides of the periphery.
See this is the thing, when you are clueless, best to keep quiet, rather open your mouth and prove to the world how clueless you really are.
1) Riverine Terrain does not mean it cannot be controlled. You just use different techniques, even basic ones like K-9 units helps!
Secondly, Whatever uninhabited area that is not low lying, should have been mined. But neither of these options have been utilized. No point in going to Night vision /Thermal / CCTV Cameras, drones or other simpler things like observation posts.
2) You are talking nonsense. 26km circumference is NOT impossible / difficult for K-9 units. You start at the perimeter and work your way in. Simple as that. This is one of the missions K-9 units train for. Even simpletons like Military Police use them exclusively as guard dogs.
3) Forget using, have you ever even held a NVG/ Thermal Camera in your hand? How come Helicopters, or drones, with FLIR weren't deployed? Lastly, why is the base overrun with vegetation, that has proven to be a nuisance?
Sorry to say, but any which way you look at it, very poor performance. The myth of invincibility destroyed, by a handful of rag tag nobody's.
IF
proper accountability is to be done, heads would roll, right from the BSF sector in-charge., to the base commander, and so on, and so forth.
Lets see how this pans out.