Why was the signing of a trade treaty with the US in 1854 so contentious in Tokugawa Japan?

by argumentativ

It seems like letting ships into your ports wouldn't be a big deal for an island country. Why was it such a big deal for the shogunate to sign the treaty?

OldWorldGlory

You might be interested in threads from the FAQ sections on "Sakoku aka Edo Period Japanese 'Isolation'", "Sakoku and Dutch trade" and "Commodore Matthew Perry and the opening of Japan":

Commodore Matthew Perry and the opening of Japan

On the Edo Period Late Tokugawa Japan