I came across one person on the internet who denied that the Democratic and Republican parties had ever switched political platforms. In response, I cited the passing of the Sherman Antitrust Act in 1890 (Intended to limit the growth of monopolies, and was introduced by a Republican senator and signed into law by a Republican president) as evidence that the Republican party was not always pro-small government. What are some other examples I could have used? Could you give me some instances of the Democratic or Republican doing something (passing a bill, supporting an action) that they would not have supported nowadays? I'm honestly quite curious.
The party switch isn't something that happened overnight -- for an example, the Republican party was the party of abolition and African-American rights in the 1860s, but most Republicans very much not in support of the Civil Rights movement by the 1990s. There's plenty more here.