► 形容動詞無謀  [むぼう]    
meaning:  reckless  rank: 3☆ 
我々だけで
相手の
基地を
攻撃するのは無謀だ ⇨ It’s reckless and stupid for us alone to attack the enemy base. There’s no hope of success
More examples:- 徐々に変えるなら未だ分かるが、一度に全てを変えるのは無謀だ ⇨ It is doable if we change things gradually, but change everything all at once is stupid