Major and oldest port, Kolkata has the Ordnance Factories Board of the Ministry of Defence, the Garden Reach Shipbuilders & Engineers and the Eastern Command of the Indian Army are all headquartered in the city.
The Consulate General in Calcutta serves the states of Bihar, Jharkhand, Odisha, West Bengal, Sikkim, Assam, Meghalaya, Tripura, Mizoram, Manipur, Nagaland and Arunachal Pradesh. All these are badly troubled regions of India, easier to get them independence. Kolkata / Calcutta is major target of Pakistan.
And I like the harmless Calcutta girls getting freed.