It seems to me that the two-party system in the United States is, practically speaking, the same thing. Within each major party there are smaller caucuses, such

It seems to me that the two-party system in the United States is, practically speaking, the same thing. Within each major party there are smaller caucuses, such as the Freedom Caucus, which are more extreme than the party as a whole and exercise outsized influence because the larger party needs them to maintain its big tent. "Big tent" == coalition.