From Emperor of Japan: Meiji and His World, 1852–1912, by Donald Keene (Columbia U. Press, 2005), Kindle p. 30:
Two days after Harris’s arrival in Shimoda , Jan Hendrik Donker Curtius (1813–1879), formerly the chief merchant of the Dutch trading station on Deshima but now the Netherlands government commissioner, sent (by way of the Nagasaki magistrate) a letter to the shogunate in which he urged that the policy of the closed country be abandoned. He predicted that if Japan persisted in this policy, it would lead to war with the major countries of the world. He also called for the old regulations against Christianity to be lifted, deploring in particular, as contrary to good relations with other countries, the use of fumie (images, generally of the Virgin Mary) that the Japanese were obliged to tread on to demonstrate that they were not Christians. He pointed out the advantages to Japan of trade with foreign countries and advised the Japanese to set up a schedule of import duties and encourage the production of wares suitable for export. He suggested also that men from countries with relations with Japan be permitted to bring their wives and children to live with them in the open ports. Finally, Curtius asked that the restrictions on foreign ships be lifted and the laws revised with respect to permission to leave the ports and to travel to Edo.
Twelve years earlier (in 1844) Willem II, the king of Holland, had sent a letter to the shogunate asking that the country be opened to trade. The haughty officials did not deign to respond, but since then the situation had changed dramatically, and the shogunate now felt that it had to give serious consideration to Donker Curtius’s suggestions. At the council meeting, virtually all those present spoke in favor of opening the country speedily. Only Abe Masahiro, worried about the reactions of the various domains and fanatical patriots, said that the time was not yet ripe for such action. No one defended the longstanding tradition of the closed country. The shift in policy had occurred with startling swiftness.