Chamberlain desired an imperial federation formed on the model of Bismarckian Germany to allow Britain to maintain its global role amidst the growing economic challenge of the United States and Germany. He wanted Imperial Preference in trade with the empire and tariffs on foreign imports. Chamberlain also believed that tariffs would generate finance for a scheme of old-age pensions and other social improvements. Such a programme would help Chamberlain secure the Unionists' hold on the West Midlands, and further enhance his power within the government. Chamberlain prepared to end the Free Trade consensus that had dominated British economics since the repeal of the Corn Laws in 1846.