The only way that a man can wage war with this powerful desire is by removing from himself these two aspects (1. improper sights and 2. lustful thoughts). And by doing this, one instills within himself that he should not lust after this, and he will be able to control his natural desires. And this is the reason that Chaza"l say (Brachos 34b) "In the place that Balei Teshuvah stand, even the completely righteous cannot stand". For the natural good will of the completely righteous wins over their desires without great effort, which is not the case with a Ba'al Teshuvah.
And if one should ask, "How can a natural person be in control of his desires which "force" him to act? After all, it does not make sense that Hashem would obligate all men equally to guard themselves in this area, only people who can stand up and have the will power to deny this desire! And these are people who never came into the tests of seeing improper sights and thinking lustful thoughts. Only for such people did the Torah command these Mitzvos. But for people who already fell into these things, it is naturally impossible for a man to control himself and hold back from this craving that forces him to act!"
To counter this claim, Hashem wrote in the Torah with pleasant words of life, and the Parsha of Arayos starts out with the words "Speak to the Children of Israel and say to them, I am Hashem your G-d". For it is true that in the human race, besides for the Jewish people, they can claim this complaint and say that they did not find it in their strength to deny the power of this intense desire from themselves. However, with you, the Children of Israel, because I am Hashem your G-d - that is, you can achieve understanding and awareness of G-d - and through this G-dly strength, you will win over the natural physical drives.
The Ohr Hachayim has touched here on the "core" of the 12-Step program, which is that without bringing G-d into the picture, we are powerless to overcome this powerful desire. See also this Q&A.