However, the opening of Japan to the West had already begun in the time of Masahiro ABE, and Naosuke's forceful methods can be viewed as a detriment to a more careful plan that involved the appointment of Kaimei-ha, research of overseas situations, and prior consultation with powerful domains such as Mito, Satsuma, and even the Imperial Court.
ただし開国に関しては阿部正弘のころからの既定路線であり、それまで綿密に進められた水戸や薩摩といった雄藩や朝廷への根回しや海外事情の調査、開明派の人材登用による開国体制の構築が直弼の強引な手法により瓦解し、大混乱を招いたともいえる。