Many would write the negatives of the Sethu Samudhram project and I would agree with most of the logical and reasonable arguments (limited to economic and secuirty issues) without venturing into the cultural and religious arguments which also clearly have their merits.
But beyond all this there is one reason why the Sethu Samudhram project is a must. There was this poor politician from India. He once visited a developed country. A senior minister hosted him in his rich country house. The impressed Indian asked him how he could afford that. The Host took him to a large french window and showed him a river. He asked the Indian if he could see the bridge across the river and added “this is 10% of that”.
Few years later the Minister from the developed country retired and embarked on a world trip. He landed in India and called up his old friend. He was shocked when he was housed in a large palace. Surprised he asked his Indian friend how he could afford that. The Indian took him to a similar but much larger window and showed him a larger but much abused and dirty river and asked his Guest “Can you see that Bridge across the river?” The Guest couldn’t see any bridge and said so. The Host proudly said “This palace is 100% of that project”.
Hence Sethu Samudram is vital.