On Thursday, a passenger train set a new national record in a speed test between Delhi and Agra, running at 160 km/h and thus beating the old speed by 10 km/h. Headlines dubbed it a “semi-bullet train”.

But what is a bullet train? The term came into usage circa 1964, after the Japanese Shinkansen trains, which earned the moniker because of their distinctive aerodynamic design and speed, began operation. The top speed of the Shinkansen is 320 km/h, double the speed of the train that tested yesterday between Delhi and Agra.

There is almost no chance railways minister Sadananda Gowda will announce something along those lines in his speech on July 8, when he presents the Railway Budget: getting trains to 300 km/h or more would require laying entirely new rail lines, building new stations, buying new locomotives and rolling stock, all while finding a corridor that will provide enough viable traffic for it. Instead, the railways are more likely to push forward on what would count in India as high-speed rail. With express trains running at an average of 50 km/h and goods trains at 25 km/h, according to a reply in the Rajya Sabha two years ago, bringing trains up to even 120 km/h would count as a veritable revolution for Indian Railways.

The terms high speed rail and bullet trains are being used interchangeably, yet even high-speed rail is defined by the European Union as trains that run at minimum speed of 200 km/h. At the most, one corridor with the intent of reaching those speeds can be expected from the rail budget, unless the government also decides to allow 100 per cent Foreign Direct Investment in high-speed rail.

Does India need trains that fast? As arguments against high-speed rail in places as disparate as California and Argentina have shown, high-speed rail could be a white elephant.

It appeared to be a key talking point in Narendra Modi’s campaign, along with other promises that were sure to usher in acche din. Modi promised bullet trains that would crisscross the country, bringing an infrastructure construction boom along the lines of Japan’s post-war success. The Bharatiya Janata Party manifesto even laid out a “Diamond Quadrilateral” project of bullet trains.

Modi travelled by bullet train in Japan in 2012, taking one to visit a Suzuki plant in Hamamatsu and meet Indian engineers working there. That was not the first time an Indian leader took the bullet train in Japan.

In 2009, the then railways minister Lalu Yadav also took a bullet train in Tokyo. He wanted bullet trains in India, but railway officials seem to have found the idea not very feasible. The main concern was the high cost, but also safety. The railways seem to think it is wiser to upgrade existing rail tracks to make trains run faster, rather than create expensive new high-speed corridors. After Mamta Banerjee became railways minister in 2009, her “Vision 2020” document, presented in Parliament, promised high-speed rail, and said the railways was looking at the feasibility of high-speed rail in six corridors: Delhi-Chandigarh-Amritsar; Pune-Mumbai-Ahmedabad; Hyderabad-Dornakal-Vijayawada-Chennai; Howrah-Haldia; Chennai-Bangalore-Coimbatore-Ernakulam; and Delhi-Agra-Lucknow-Varanasi-Patna.

The Indian government began taking a serious look at the possibility of high-speed rail even before Narendra Modi became prime minister. In December 2013, a Japanese consortium was given a $5.73 million contract to study the feasibility of a high-speed rail link between Mumbai and Ahmedabad. They are to finish the study by July 2015, “including such work as projecting demand, estimating operating expenses and formulating basic plans.”