Article: While Brazil was fighting the US through the WTO's Dispute Settlement Mechanism against a heavily subsidized cotton industry, a group of four least-developed African countries Benin, Burkina Faso, Chad, and Mali also known as "Cotton-4" have been the leading protagonist for the reduction of US cotton subsidies through negotiations. The four introduced a "Sectoral Initiative in Favour of Cotton", presented by Burkina Faso's President Blaise Compaore during the Trade Negotiations Committee on 10 June 2003.

Question: What was Brazil's argument against the US cotton industry?
heavily subsidized