Yes india should have liberated Bangladesh, But the standard saying India gains in the war and losses on the table is true in this issue also. The least we should have ensured is that Bangladesh Should be guarded by Indian defence along with their defence, Should have had a corrior through bangladesh to reach the north eastern states, Should have made pakistan vacate the major part of kashmir, atleast till we have occupied the heights and a space through which a good road will be made to reach Leh, Ladakh. With none of this done It was a wasteful sacrific by the defence forces.