No banning, perhaps, but a muting, and at a most critical time--which is just as contemptible in a free society.
I am just now reading Scalia's remarkably clear and sharply focused dissent. You ought to as well. He hammers home the incumbant criticism-muting point very well.
Excerpt: "This litigation is about preventing criticism of government. I cannot say for certain that many, or some, or even any of the Members of Congress who voted for this legislation did so not to produce "fairer" campaigns, but to mute criticism of their records and facilitate reelection. Indeed, I will stipulate that all those who voted for the Act believed they were acting for the good of the country. There remains the problem of the Charlies Wilson Phenomenon, named after Chalres Wilson, former president of General Motors, who is supposed to have said during the Senate hearing on his nomination as Secretary of Defense that 'what's good for General Motors is good for the country.' Those in power, even giving them the benefit of the greatest good will, are inclined to believe what is good for them is good for the country. Whether in prescient recognition of the Chalrie Wilson Phenomenon, or out of fear of good old-fashioned, malicious, self-interested manipulation, '[t]he fundamental approach of the First Amendment . . . was to assume the worst, and to rule the regulation of political speech 'for fairness' sake' simply out of bounds. . . . Having abandoned that approach in Buckley, we abandon it much further today. . . .
"The most frightening passage in the lengthy floor debates on this legislation is the following assurance given by one of the cosponsoring Senators to his collegues: 'This is a modest step, it is a first step, but does even begin to address, in some ways, the fundamental problems that exist with the hard money aspect of the system.' The system indeed. The first instinct of power is the retention of power, and, under a Constitution that requires periodic elections, that is best achieved by the suppression of election-time speech. We have witnessed merely the second scene of Act 1 of what promises to be a lengthy tragedy. In scene 3 the Court, having abandoned most of the First Amendment weaponry that Buckley left intact, will be even less equipped to resist the incumbents' writing of the rules of political debate. The federal election campaign laws, which are already (as today's opinions show) so voluminous, so detailed, so complex, that no ordinary citizen dare run for office, or even contribute a significant sum, without hiring an expert advisor in the field, can be expected to grow more voluminous, more detailed, and more complex in the years to come--and always, always with the objective of reducing the excessive amount of speech." [emphasis added]
Having run for Congress and battled these demonic regulations and restrictions myself, I can well-identify with the bolded words. Incumbents write laws to benefit incumbents. This legislation is more of the same. Its effect will be to stifle political debate to the benefit of incumbents.