A "Progressive" (as a noun, capital P) is part of a social-cum-political movement that started roughly a century ago, plus or minus two decades.
>> Progressivism began as a social movement and grew into a political movement. The early progressives rejected Social Darwinism. In other words, they were people who believed that the problems society faced (poverty, violence, greed, racism, class warfare) could best be addressed by providing good education, a safe environment, and an efficient workplace.
Progressives lived mainly in the cities, were college educated, and believed that government could be a tool for change. Social reformers, like Jane Addams, and journalists, like Jacob Riis and Ida Tarbel, were powerful voices for progressivism. They concentrated on exposing the evils of corporate greed, combating fear of immigrants, and urging Americans to think hard about what democracy meant. Other local leaders encouraged Americans to register to vote, fight political corruption, and let the voting public decide how issues should best be addressed (the initiative, the referendum, and the recall).
On a national level, progressivism gained a strong voice in the White House when
Theodore Roosevelt became president in 1901. TR believed that strong corporations were good for America, but he also believed that corporate behavior must be watched to ensure that corporate greed did not get out of hand (trust-busting and federal regulation of business). << (
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The last guy to run for President associating with that label AFAIK was Robert LaFollette of Wisconsin (another Republican, for what it's worth which is very little) in 1924.
"progressive" on the other hand (small p) is an adjective, simply meaning "in favour of progress". Its opposite would be
regressive, which appeals to no one but Luddites and funda-mentalists. As an adective it does not get an indefinite article ("a"). Yet rhetorical wanksters on this board (Westwall comes to mind) will treat it as a noun, using it while making morphological scary faces going "booga booga", as if to connote some kind of never-defined negative. Asked for a definition that differs from the historical one, they invariably run away.
In other words they're using a term as a slur by innuendo, never bothering to define what they're talking about, simply hoping the
emotion alone will convey --- the same thing Joe McCarthy and his ilk did with the word "Liberal" in the 1940s and '50s. It is a slur told by idiots, full of sound and fury, signifying nothing.