McGovern, Kaus, impact on growth, intimidation and binding arbitration, E. Thomas McClanahan has it all in the Kansas City Star:

For decades, workers’ decisions on whether to unionize have been expressed in secret-ballot elections supervised by the National Labor Relations Board. At stake in the presidential campaign is whether to do away with that process — by passing a misnamed bill called the Employee Free Choice Act.
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Certainly, some companies have such lousy labor relations that they deserve to deal with unions. But given the opportunity for face-to-face intimidation and pressure, EFCA — also called the card-check bill — would greatly increase the number of union shops in the country, retarding economic growth.

It’s no accident that many of the innovations we take for granted today largely arose from companies that were not unionized. Unions oppose technological changes that upset the status quo. They seek to keep work confined within existing categories. They undermine productivity, the source of rising living standards.