For Japan and South Korea, tariffs announced by U.S. President Donald Trump represent a blow to domestic car industries that are both economic pillars and sources of national pride.

Shares in companies such as Japan's Toyota and Honda and South Korea's Hyundai Motor and Kia fell, wiping off some $16.5 billion in value, after Trump on Wednesday unveiled a 25% tariff on imported cars and light trucks to take effect on April 3.

On the streets of Tokyo and Seoul, and in "motor city" Gwangju, people were concerned the levies would have a far-reaching impact, speaking to the singular role the car industry has played in the postwar economic rise of the two U.S. allies.