> America has not seen a long-lasting national third-party movement in its history, and it won't be seeing one now. I don't agree. True, it's been a long time.

> America has not seen a long-lasting national third-party movement in its history, and it won't be seeing one now. I don't agree. True, it's been a long time. The Democratic and Republican parties have dominated U.S. politics for over 150 years. But the country is older than that. Before the mid-1850s the Whigs were a major force; the Republican Party started as a "third party". So, earlier, did the Whigs, eventually displacing the Federalists. It is true, however, that the U.S. has never seen three major parties being powerful at the same time. When a new party has become powerful, an old one has always faded away, leaving just two.