In the long term, SOPA creates an opportunity for the rest of the world. It highlights the dangers of having so many important services—Google, Bing, PayPal, Visa, MasterCard—concentrated in a single jurisdiction, such that a single law can take down all the services together. In turn, this creates a demand for a non-American search engine, a non-American ad network, a non-American payment network. America’s loss should be the rest of the world’s gain.
In the short term, given the absence of credible competition to these American services, the potential for severe disruption with no effective means of redress is enormous.