I cannot grasp what にも means between 身のほど知らず and 敵対する愚 in the following sentence, maybe something like "foolishness of taking up arms not knowing their place" ?
As far as I can understand the sentence: "Let them taste true fear. Make them remember the foolishness of (身のほど知らずにも) taking up arms against our nation and our people, and then allow them to savor their bitter victory!"
奴らには恐怖を与えろ。この国に、我々に、身のほど知らずにも敵対する愚を思い知らせ、後に矮小な勝利をくれてやれ。
Thank you!