He then moved to Berlin. The (liberal) merchants in the port cities of Prussia suffered from the protectionist measures of the Zollverein, and Prince-Smith soon found himself politically involved, becoming one of the more outspoken proponents of Manchester capitalism  free trade. Prince-Smith believed protectionist tariffs to be harmful in general, and argued that worldwide free trade would lead to universal peace.
He moved to Berlin, where merchants in Prussia's port cities faced challenges from the Zollverein's protectionist policies. Prince-Smith became politically active, advocating for Manchester capitalism's free trade principles, believing tariffs were detrimental and that global free trade would lead to peace.