Habakkuk’s first protest was about seeing all the injustice that was being committed within the people of Judah and seeing no sign from God of judging such a nation. And so he wanted an answer from God, when He was going to judge Judah.
After the first protest, God told the prophet that He would judge Judah through the Chaldeans, an extremely idolatrous and corrupt nation. Undoubtedly, this was very shocking to him, because, no matter how much Habakkuk wanted the injustice of his nation removed, he also did not want them to be judged by a nation much more corrupt than them.
12 Art thou not from everlasting, O Lord my God, mine Holy One? we shall not die. O Lord, thou hast ordained them for judgment; and, O mighty God, thou hast established them for correction.
13 Thou art of purer eyes than to behold evil, and canst not look on iniquity: wherefore lookest thou upon them that deal treacherously, and holdest thy tongue when the wicked devoureth the man that is more righteous than he?
14 And makest men as the fishes of the sea, as the creeping things, that have no ruler over them?
15 They take up all of them with the angle, they catch them in their net, and gather them in their drag: therefore they rejoice and are glad.
16 Therefore they sacrifice unto their net, and burn incense unto their drag; because by them their portion is fat, and their meat plenteous.
17 Shall they therefore empty their net, and not spare continually to slay the nations?
Habakkuk 2:12-17