Then, we have scientists who make models which should be falsifiable, but instead of declaring that the models don't work when they fail to match reality, they make adjustments to "fit the curve". Anyone who has dealt with models before knows that you can make any number of adjustments to fit any curve you want. After the adjustments, the models continue to be inaccurate. Sometimes, suspiciously, the models become more accurate in the near term but still predict the same huge temperature rise in the future.
Then, the activists on the left take the current claims made by science and extend them as far as possible. This is then stated as fact. See: Al Gore. Said activists use "97% consensus" to defend their hyperbolic claims, mostly knowing that the 97% consensus doesn't apply to their exaggerations.
These "facts" are then used as justifications for massive government involvement in the economy, which just so happens to line up with the political wishes of the left.