Final answer:
The 'new era of permissiveness' refers to a time when societal norms were becoming more liberal, especially among the youth, which is reflected in the Supreme Court's protection of student expression in Tinker v. Des Moines.
Step-by-step explanation:
The term "the new era of permissiveness" referenced in relation to the Tinker v. Des Moines case, likely alludes to a period in which societal norms and expectations, particularly among young people, became more liberal and accepting of a broader range of behaviors and expressions. The case itself, which occurred in 1969, is a significant example of this shift, wherein the Supreme Court upheld the rights of students to wear armbands as a form of protest, illustrating a recognition of First Amendment protections even within the context of a public school setting. This was indicative of a broader trend towards greater personal freedoms and the questioning of traditional authorities during the 1960s, an era that also contended with issues such as the new morality and challenges to established norms.