For example, let’s say Bernie Sanders was the nominee in 2024 against Trump. A lot of people on the internet seem to like him, even some conservatives. But would liberals fall in line and vote for him enough to beat Trump?
Bernie’s supporters always seem to attack the Democrats liberal base, do you think they’d sit home if Bernie or any leftist was the nominee.
In the context of Germany, “liberal” means being for capitalism unbridled by the state but still generally progressive policies culturally, with more rights for minorities and such. The corresponding party is FDP.
Someone considered “left” would be for more social policies and government control of capitalism (traditionally SPD), extreme left would be following tenants of communism, opposed to the US and friendly with Russia (The party The Left and the new Sarah Wagenknecht party)
Someone considered conservative or “right” would be against social policies and try to reduce control of capitalism (CDU) extreme right would be plain fascists (AfD), ironically also aligned with Russia now.
The Greens are a special case, since they were originally a single issue party concerned with environmentalism, but since the SPD has largely vacated their social policies since Schröder was chancellor, they have become more and more the new “social” party.