India's North East part is almost detached from mainland due to Bangladesh border in between. Pakistan on the other hand shares just one side border with India. If anything happens in Pakistan it will not affect India much but if anything unexpected happens in Bangladesh it will severely affect North east India. There are anti-India terrorist organizations like Lashkar E Taiba and HuJi who use Bangladesh route to attack India when BNP-Jamaat in power. Recently RAB, the elite force in BD found 5 big bunkers and one military base of ULFA terrorists who got save shelter in Bangladesh during BNP-Jamaat regime who planned a mass genocide in India with these weapons. High court of Bangladesh recently gave death sentence to many ULFA terrorists and some BD terrorists who were involved in this plan including BNP minister and Jamaat chief.
https://defence.pk/threads/breaking-news-rab-has-found-ulfas-5-big-bunkers-and-1-military-base.317183/
Bangladesh is extremely critical neighbor for economic reason also. India has a tiny Shiliguri corridor to reach NE India. That region is underdeveloped. India requested Bangladesh to give a transit access through Bangladesh to go to North East region which is almost double in size than Bangladesh but its a matter of great debate in Bangladesh whether to give the access facility to India because Bangladesh is at risk of total Indian invasion since independence due to geo-strategic position. Some suspect India will invade Bangladesh through this access, some say India will make Bangladesh its 29th state by getting this transit in Bangladesh but AL govt. is determined to give the road transit and power corridor for development.
Dhaka agrees to provide power corridor to India -
bdnews24.com India also wants rail corridor in Bangladesh to reach NE region.
Migration problem is another serious issue India is facing in Indo-Bangla border area. India Bangladesh border is not the same border any other two countries share with each other. Its very superficial border because the border is disputed since 1971. Both countries are not ready to give up land to resolve enclave issue. Inside Bangladesh there is an Indian village and inside that village there is a Bangladeshi village and inside that area there is another Indian area. Its very weird border. So migration to India and vise versa is very easy. There are also rivers connecting India and Bangladesh. Many migrants use river channel. So migration will continue forever because you can not fence river.
Illegal Bangladeshis going to India for searching jobs.
Narendra Modi's Bangladesh pitch requires a Moditva approach, not Hindutva | Latest News & Updates at Daily News & Analysis
So, the conclusion is its not Pakistan its Bangladesh which is the most critical neighbor of India.
