Who said "One must understand the enemy to defeat him."?

This quote is attributed to Zemo.

One must understand the enemy to defeat him. - Zemo

"One must understand the enemy to defeat him."

Zemo

"The world has always belonged to the powerful. We just had to remind everyone."

"Bucky Barnes was a weapon. Now he is free. That is what matters."

"You cannot build a new world without breaking the old one."

"Empathy is a tool, nothing more. Use it wisely."