UStrade sanctions have applied to Iran since 1996. One goal of denying that country’s national oil company access to American goods, services, and technology has been to punish its government for allegedly trying to gain nuclear weapons.Several members of Congress now want the US to be ready to turn up the heat. They’ve introduced bills in the House and Senate that would bar foreign suppliers of refined products to Iran from effectively doing business in the US.HR 2194, which Rep. Howard L. Berman (D-Calif.) introduced on Apr. 30, also would apply to any non-US firm which finances, brokers, underwrites, or provides ships to help Iran import refined products. It also would appl...