Before the <i>Citizens United</i> case came down, thousands or millions of people <i>were</i> free to get together to say the same thing at the same time by donating money to organizations (“527 corporations”) whose specific purpose was political advocacy.  (Or they could give money directly to their favorite political parties or candidates, but then each person involved faced limits on what he or she could contribute.)<p>What <i>wasn’t</i> legal was for another kind of corporation to use its general-treasury funds for the same purpose.  The laws banning that kind of spending were based on the idea that when a for-profit corporation injects itself into the electoral process¹, it creates the appearance of political corruption if not actual corruption.  After all, if the corporate directors authorizing the donation <i>didn’t</i> expect to get some kind of benefit from the politician in return, then they were wasting their stockholders’ money.<p>The majority in <i>Citizens United</i> acknowledged that preventing the appearance of corruption was a legitimate concern (which is why restrictions on <i>direct</i> donations to political parties and candidates were allowed to stand), but was so committed to the “treat corporations as people” principle that they didn’t see the point of restricting contributions from corporations.<p>¹I.e., corporations <i>could</i> run ads saying “nuclear energy is great”, but <i>not</i> “vote for Smith, because he supports nuclear energy”.