What about drinking? or drugs? dangerous driving? cheat on tests? Do you teach your kids to totally refrain from these activities or just "be careful".
Why is sex different when the risks can be so much more harmful? Maybe your attitude will change when you read this.
People seem clueless that sexually transmitted diseases such as herpes, gonorrhea, chlamydia, and human papillomavirus can take hold in parts of the oral cavity during sex with infected partners and that the oral contact can infect the genitals, too. HPV is a particularly scurrilous threat, since it incubates silently in the back of the mouth and is now linked to a dangerous form of throat cancer in both men and women similar to the one that arises in the cervix.
So I guess a "progressive" would offer that catching HPV in your throat is practicing safe sex.