I didn't read everything, so please forgive. But during it's isolationism period, Japan ONLY traded on it's terms. Any attempted violations suffered various forms of death. Even shipwrecked sailors were included in this ends. The Japanese did trade with the Dutch, but there were almost no other exceptions...... until Commander Perry sailed into Edo Harbor with those warships belching out all that smoke.
Fast forward to today, it seems many east asian nations are very interested in moderism, as displayed by the insatiable appetite for all the electronic gagets that are snapped up, wholesale by it's youth.
The Japanese also had extensive trade with the Koreans and the Chinese, and had established relations with these two countries that extended for centuries. It is true that the nature of those relations rose and fall sharply at various times, but they were there and were important. The Japanese isolation was internally focused. That is, the government controlled all contact and trade between foreigners and the Japanese population. A population ignorant of the outside world, in theory, is easier to control. There were also periods where this contact was expanded (such as with Jesuit missionaries) and subsequently tightened (executing all the Jesuit missionaries and their followers). But, it was not static in its nature, nor was it even near total isolationism.
The biggest weakness in the bakufu/shougunate government was their socio-economic policies separating the merchants and the warriors. There were so many fiscal responsibilities heaped upon the ruling warrior class during the Tokugawa era coupled with prohibitions against the warrior class engaging in commerce, the shogun and the daimyo were economically crippled by the time of Admiral Perry's 'visit'. Desires aside, they simply had no capability of engaging in development to match pace with the U.S. as there existed neither the money nor the infrastructural development because of social and fiscal constraints. I don't think it was a philosophy against modernization in general that was the problem. Indeed, you might want to read up on Tokugawa Yoshinobu, the last shogun of the Tokugawa shogunate. He actually had engaged in active reform and international diplomacy during his ill-fated reign. Perhaps if only he hadn't turned to the French . . .