A fence that was supposed to take a few construction seasons to build turned into one of the longest running conflicts ever between the Centre and a state government and lasted for more than 10 years. Amit Shah, Union Home Minister, took the opportunity of the ground breaking ceremony of the new projects of Sashastra Seema Bal on Friday at the force's border headquarters in Siliguri to remind the gathering of that history, saying that his repeated appeals for land to fence the Indo-Bangladesh border in West Bengal had remained unanswered for years under the previous Trinamool Congress government. He claimed that he has been trying to buy 1129 acres since 2014 and the land was only seeing movement after Suvendu Adhikari's BJP government came to power in the state in May.

There's some hard data behind that grievance, and it's worth spelling out here, as it is relevant to the fact that the argument persists across election cycles. The state of West Bengal has 2216 km border with Bangladesh, which is the longest border with any other state in the country. Of this, approximately 1648 km have been fenced over the years with approximately 568 km remaining unfenced. Out of that unfenced area, almost 112 kilometres was unfeasible due to rivers, char lands, shifting terrain and so on, but the remaining 456 kilometres were fenceable so far, but simply languished in the queue for land acquisition, compensation issues and, in the story-telling of Delhi, plain political reluctance. In the past two years, successive data on unfenced areas of the country supplied to Parliament indicated the unfenced length of the country's total boundary of 4,096.7 kilometres was around 864-865 kilometres, leaving Bengal with well over half of the unclosed length of the international border.

When politics shifted, the change was quick. After the BJP won the assembly elections with a landslide, Adhikari, sworn in as chief minister on May 9, handed over an initial 27-kilometre stretch of about 75 hectares to the Border Security Force within 11 days of assuming the office stating it was the first step towards settling the delayed backlog within a year. By the end of May, the count had surpassed 142 acres, and the government's release of data in June revealed that the Trinamool government had handed over almost 395 acres in the past seven years, and the new government had secured nearly 475 acres in just six weeks. Ground officials have admitted the reason of the old delays wasn't entirely political some of the disputed land was owned by people who objected to the land acquisition; some alleys also went deep into the fields well beyond the boundary line, irrespective of the ruling political party in Kolkata. However, the speed with which the past three months have occurred is hard for anyone to call random.

The significance of any of this goes beyond the borders of Bengal: it is for those who follow the economy of the region, not its politics. The Indo-Bangla border is not only a boundary between two countries, but it is also a hub of one of the biggest informal economy in South Asia. Estimates by the own revenue authorities of the government and independent researchers in Bangladesh place the volume of unrecorded, cross-border trade at between four and eleven billion dollars per year mostly from India into Bangladesh via the same porous regions that have been the focus of this political debate. Cattle are a trade estimated in the hundreds of millions of dollars a year, and the simple economics of a beef-consuming neighbour adjacent to a country that has an export ban and abundant supply of cattle. On top of that, there is the continuous stream of narcotics, fake money, weapons and, more and more, fake identity papers that can get through a gap in a fence, but not through a manned one. Figures presented to Parliament by the home ministry indicated that contraband seizure on this border in one recent year was more than 461 crore rupees, the highest in ten years, and this year's Union budget provided nearly 5,577 crore rupees to the border infrastructure and management, of which capital spending on smart surveillance systems, sensors and modernisation has been kept higher.

The part of the debate that is all too often lost in the back-and-forth of political blame. A fence is not just a piece of security paraphernalia for an election rally, it is infrastructure that will affect by how much of a state's shadow economy will remain hidden and by how much of it can be made visible and liable to be taxed, regulated or even closed for policy reasons. Each kilometre left open is a subsidy to the smugglers on either side of the line, and every seizure reported by the BSF is a small fraction of what is likely to have got through unnoticed. From that perspective, the battle for 1,129 acres of Bengal farmland was no mere optics game before a vote, it was a battle for control of a multi-billion-dollar informal economy on the eastern edge of India and over how the state's demographics and economics evolve, whether by osmosis or by policy.

The next will be the test of execution and not promises. Adhikari's government has pledged to finish fencing along the practicable sections within a year and the Centre has committed to speeding up clearances from its end. But whether that time frame will hold true if it gets the same treatment from the same land and the same compensation battle as the previous government, is a question that will be decided by the voters of the border regions and not by the Delhi press or the Kolkata crowd.