What is the march on the salt depot supposed to prove? Ghandi!!!?

Gandhi led his followers in the Non-cooperation movement that protested the British-imposed salt tax with the 400 km (240 mi) Dandi Salt March in 1930. It was a campaign of nonviolent protest against the British salt tax in colonial India. Mahatma Gandhi led the Dandi march from his Sabarmati Ashram to Dandi, Gujarat to produce salt without paying the tax, with growing numbers of Indians joining him along the way. When Gandhi broke the salt laws in Dandi at the conclusion of the march on April 6, 1930, it sparked large scale acts of civil disobedience against the British Raj salt laws by millions of Indians. The Salt Satyagraha campaign was based upon Gandhi's principles of nonviolent protest called satyagraha, which he loosely translated as "truth-force.