Japan's maritime history can be traced at least as far back as the first millennium, but the country did not fully emerge as a significant naval power until the Meiji Restoration. As an industrialized nation, Japan relied on maritime commerce to acquire the resources it needed to develop a powerful economy and a navy capable of protecting Japan's all-important sea lines of trade and communication. Japan's reliance on foreign trade and maritime commerce only grew as Japan emerged as a great economic power in the post-World War II era. The Japanese sea lines of communication are deemed critical security concerns because Tokyo remains reliant on the import of energy, minerals and food, as well as the outward shipment of manufactured goods. In terms of volume, almost all of the country's trade is seaborne. The existence of Japan as we know it depends on these maritime trade routes.