Wrath, as you stated is not sinful, simply because it is wrath. As such there is a righteous wrath that stems from a Holy God, and was also demonstrated through His only begotten Son, Jesus Christ. God's wrath has been evident in the past, and is the same wrath that His only begotten Son, Jesus Christ demonstrated. God does not *wink* at wickedness, nor does He allow those seeking to shed innocent blood, go unpunished. God is perfectly just, and just as He enabled David to boldly approach Goliath (who had the entire king's army hiding and quaking in their armor), and told him that he was going to slay him in the name of, and for the sake of the God of Israel, and then did, and then cut off the giant's head, God has rose up other mighty men of valor throughout history.
They do not back down from evil, but put a stop to it, and at the unction of a holy and a just and righteous God, Who loathes the evil that is behind the plotting of doing harm to an unsuspecting victim. It's all throughout God's Word.
We are to take a stand against evil and speak out for and defend those who cannot speak out for or defend themselves.
It is not a sin to take a stand against evil and to put a stop to it. It is righteous and valiant thing to do. To stand by and allow evil is akin to bowing to evil and becoming a pawn in its effort to cause harm and the demise of innocent parties.
To stand by and allow evil is a sin.
Thank you kindly.
"It is a fearful thing to fall into the hands of the living God." ~Hebrews 10:31