From the Morse v Fredrick decision
The Vietnam War is remembered today as an unpopular war. During its early stages, however, “the dominant opinion” that Justice Harlan mentioned in his Tinker dissent regarded opposition to the war as unpatriotic, if not treason. 393 U. S., at 526. That dominant opinion strongly supported the prosecution of several of those who demonstrated in Grant Park during the 1968 Democratic Convention in Chicago, see United States v. Dellinger, 472 F. 2d 340 (CA7 1972),and the vilification of vocal opponents of the war like Julian Bond, cf. Bond v. Floyd, 385 U. S. 116 (1966) . In 1965, when the Des Moines students wore their armbands, the school district’s fear that they might “start an argument or cause a disturbance” was well founded. Tinker, 393 U. S., at 508. Given that context, there is special force to the Court’s insistence that “our Constitution says we must take that risk; and our history says that it is this sort of hazardous freedom—this kind of openness—that is the basis of our national strength and of the independence and vigor of Americans who grow up and live in this relatively permissive, often disputatious, society.” Id., at 508–509 (citation omitted). As we now know, the then-dominant opinion about the Vietnam War was not etched in stone.
Reaching back still further, the current dominant opinion supporting the war on drugs in general, and our antimarijuana laws in particular, is reminiscent of the opinion that supported the nationwide ban on alcohol consumption when I was a student. While alcoholic beverages are now regarded as ordinary articles of commerce, their use was then condemned with the same moral fervor that now supports the war on drugs. The ensuing change in public opinion occurred much more slowly than the relatively rapid shift in Americans’ views on the Vietnam War, and progressed on a state-by-state basis over a period of many years. But just as prohibition in the 1920’s and early 1930’s was secretly questioned by thousands of otherwise law-abiding patrons of bootleggers and speakeasies, today the actions of literally millions of otherwise law-abiding users of marijuana,9 and of the majority of voters in each of the several States that tolerate medicinal uses of the product,10 lead me to wonder whether the fear of disapproval by those in the majority is silencing opponents of the war on drugs. Surely our national experience with alcohol should make us wary of dampening speech suggesting—however inarticulately—that it would be better to tax and regulate marijuana than to persevere in a futile effort to ban its use entirely.
the entire dissent is not long, or hard to follow. It is damn good reading.