"If South Vietnam falls to the Communists, every other nation in Southeast Asia will follow, including Australia."
* The "TWO WRONGS MAKE A RIGHT" deception.
"It is all right to execute prisoners because South Africa does it too."
EMOTIONAL TACTICS.
* The "ATTACK THE SPEAKER" diversion.
This fallacy is known as the AD HOMINEM fallacy.
"The mayor proposes opening a day care center for city hall employees. The mayor was once divorced. The mayor is not competent to make family decisions."
The mayor's willingness to please his employees and his administrative competence are diverted with a personal attack.
* The "COMMONLY ACCEPTED PRACTICE" deception.
This deception often is designed to make an action seem biased or prejudicial.