[zhemao]

Uh. Are you thinking of Japan? The Qing dynasty was brought down by more than just a few gunships.

Though the larger point about isolationism is still valid.

[em3rgent0rdr]

I wouldn't consider China to be isolationist, because China's history is full of foreign interaction.

The reason China fell back and lost the Opium Wars was not due to isolationism, but rather because for some other reason(s), they missed out on the industrial revolution. But the exact reasons(s) they missed out on the industrial revolution is a great debate, and is the quadrillion dollar question...