US Republicanism is not just "like" fascism. It is fascism. It fits criteria of Umberto Eco's 1995 definition.

Based on Wikipedia:
  • The Cult of Tradition, combining cultural syncretism with a rejection of modernism.
  • The Cult of Action for Action's Sake, which dictates that action is of value in itself, and should be taken without intellectual reflection. This, says Eco, is connected with anti-intellectualism and irrationalism, and often manifests in attacks on modern culture and science.
  • Disagreement Is Treason - fascism devalues intellectual discourse and critical reasoning as barriers to action.
  • Fear of Difference, which fascism seeks to exploit and exacerbate, often in the form of racism or an appeal against foreigners and immigrants.
  • Appeal to a Frustrated Middle Class, fearing economic pressure from the demands and aspirations of lower social groups.
  • Obsession with a Plot and the hyping-up of an enemy threat; this often involves an appeal to xenophobia with an identification of there being an internal security threat; Eco cites Pat Robertson's book The New World Order as a prominent example of a plot obsession.
  • Pacifism is Trafficking with the Enemy - because "Life is Permanent Warfare", there must always be an enemy to fight. This leads to a fundamental contradiction within fascism: the incompatibility of ultimate triumph with perpetual war.
  • Contempt for the Weak - there is not much empathy for the poor, the mentally ill, the disabled.
  • Selective Populism - the people have a common will, which is not delegated; this casts doubt upon democratic institutions, where leaders and government are seen to "no longer represent the will of the people".
  • Newspeak - fascism employs an impoverished vocabulary in order to limit critical reasoning.
  • Non-truths - lying and spreading of propaganda.

Update – December 4, 2020: Five years later shows a clearer perspective. It's not one political party that's fascist. The fundamental principle of fascism is when the corporation is the state. In 2015, the Republican Party looked more fascist than the Democrats, but in fact both were fascist and there was no alternative. With Trump's election in 2016, the Republican party became reluctantly a home once again for individualist principles that underlie the founding of the US.

In December 2020, it is clear that the Democratic party is 100% fascist. The Republican party is partly fascist – to the extent it sides with corporations, backstabs Trump, and denies overwhelming evidence of outright election fraud.

It is clear now that both the Democratic and the Republican party have been compromised for at least 20 years, and that the US has been descending into Chinese-style totalitarianism as ever more a corporatocracy, and ever less a republic.

The 2020 election is the breaking point where the US decides whether we want corporate totalitarianism, or a free country. Make no mistake: it is the Trump faction which stands for the free country – not Republicans as a whole.