anglo-irish treaty china comparative advantage corn laws dictator economic nationalism first world foreign policy free trade hai jin hongwu emperor imperium irish free state irish neutrality japan korea mercantilism ming dynasty monroe doctrine navigation acts netherlands new zealand labour party non-intervention non-interventionism power politics protectionism qing dynasty realpolitik republic of ireland robert muldoon sakoku self-defense stanford university press tokugawa shogunate united kingdom united kingdom of great britain and ireland united states united states non-interventionism wokou world war ii zheng he