NAACP v. Alabama (p.1525)

Why does the First Amendment protects the right of expressive association?

The idea is that effective advocacy of a particular point of view is “undeniably enhanced by group association.”  Thus, the freedom to engage in association for the advancement of beliefs and ideas is an inseparable aspect of freedom of speech. A, B, and C have the right to speak as individuals as well as the right to come together and speak as a group.

 Why is member anonymity critical to the right of expressive association? What might happen to NAACP members in Alabama in 1958?

Casebook p. 1525-1526:

" Petitioner has made an uncontroverted showing that on past occasions revelation of the identity of its rank-and-file members has exposed these members to economic reprisal, loss of employment, threat of physical coercion, and other manifestations of public hostility. Under these circumstances, we think it apparent that  compelled disclosure of petitioner’s Alabama membership is likely to affect adversely  the ability of petitioner and its members to pursue their collective effort to foster beliefs
which they admittedly have the right to advocate, in that it may induce members to withdraw from the Association and dissuade others from joining it because of fear of exposure of their beliefs shown through their associations and of the consequences of this exposure."