Why do I say this? Well, consider it in the light of the following.
1. Impurity destroys marriages: Addiction to pornography causes a person to objectify the human body and human sexuality. Sex loses it's procreative and unitive purpose ("babies and bonding") and becomes a simple means of selfish gratification. Husbands (and in some cases wives) become increasingly dependent upon sexual pleasure. Over time, the demand for more sexual pleasure places a strain on the marriage, causing the impure party to seek pleasure outside the marriage (in a worst case scenario) or takes one into more sexual sin which places even more strain on the marriage until it finally breaks. The fact that America's rampant divorce rate jumped when the "Sexual Revolution" of the 1960s came about speaks for itself.
2. Impurity warps one's view of human sexuality: God created sex, and as such, it is good. But He created it with for two very specific purposes, as explained in the Catechism of the Catholic Church:
"Sexuality, by means of which man and woman give themselves to one another through the acts which are proper and exclusive to spouses, is not something simply biological, but concerns the innermost being of the human person as such. It is realized in a truly human way only if it is an integral part of the love by which a man and woman commit themselves totally to one another until death....The spouses' union achieves the twofold end of marriage: the good of the spouses themselves and the transmission of life. These two meanings or values of marriage cannot be separated without altering the couple's spiritual life and compromising the goods of marriage and the future of the family. The conjugal love of man and woman thus stands under the twofold obligation of fidelity and fecundity. (CCC 2362-2363)Sex was created for the twofold purpose of procreation and unity of the spouses in the context of a valid marriage between one man and one woman; for the transmission of new life into the world, and for the purpose of bringing the spouses into an act of self-giving love for each other. Sex is sinful when it is sought for any other reason. This is why lust is considered to be such a grave sin; the seeking of sex for the purpose of selfish satisfaction of one's own pleasure perverts the sexual act away from its God-ordained purposes and destroys the notion of sex as a life giving act in the mind of the person. The more impure acts one indulges in, the worse this perversion gets.
3. Impurity destroys the ability of a person to form healthy relationships: Sexual pleasure is a very powerful force. If it is not tempered by proper sexual morality, formed in accordance with Christian virtue, it is like an addiction; like drugs, one must seek out more sexual impure acts in order to feed one's addiction. Such a need makes it impossible to form meaningful relationships with members of the opposite sex; one's perception is destroyed by their addiction, and they see them not as a human worthy of dignity, but as an object to be used for their own pleasure.
4. Impurity is spiritually lethal: Pornography, lust, fornication, masturbation, and others are all mortal sins because they are a misuse of the sexual faculty by taking sex outside of its purpose; "babies and bonding" in the context of a marriage between one man and one woman, as explained in the above paragraphs. But even more devastating is the fact that lust and others are "gateway" sins. From personal experience, these sins led me to commit even greater sins because the grace that was once present in my soul was no longer there; mortal sin had removed it. This is true for others; sexual addiction leads one to commit more and more sin in order to feed it. Only the saving grace of Christ can help the person.
Impurity is not just something we can ignore. It's something that eats away at us, and can destroy the way we look at sex. The only cure for impurity is a return to chastity and the observance of Judeo-Christian sexual values. Our society is in desperate need of such a return.
Time to get to work, I think.