I'm playing a historical visual novel set during the last years of the bakumatsu period, following a romanticised version of the Shinsengumi (Hakuoki), and I'm a bit confused on something.

As far as I understand, the Imperialist National Party's forces (anti-Shogunate, very critical of foreign influence in Japan), specifically the Satsuma-Choshu, defeated the bigger Shogunate armies by using western military tactics and weapons like canons and rifles. And this is largely why those wielding weapons of the older age (swords, spears) lost to them. I'm talking specifically of the battles in 1867 and 68, I think.

But I don't understand why the Satsuma-Choshu used these new foreign military weapons when ideologically, they were fiercely against any foreign influence in Japan. Isn't that hypocritical? Or am I missing something?

(Sorry for any factual errors, I'm just going off of what I could glean from my own searches and the in-game encyclopedia. Thank you!)