Think of it this way. Climate change is a cliff, and the human race is in a car racing toward the edge at high speed. So what to do about it?
Climate realists* say we should slow down (reduce fossil fuel use), and change direction (switch to clean energy).
Climate denialists deny the very existence of the cliff. They are not sure if it's a mirage or a conspiracy, but they are sure that it isn't real. According to them, we should all just quit worrying, sit back and enjoy the ride. Unfortunately, they ignore the fact that over 97% of published climate scientists (the ones doing the actual research on the lab bench and in the field) agree that human-caused climate change is a real problem.
The lukewarmers say that it's not a cliff, just a little speed bump in the road, not that big a deal. If we listen to them, all we have to do is put new shocks on the car, and then it's hey, full speed ahead! The problem here is that the latest scientific research refutes the claim of low climate sensitivity (warming in response to a doubling of atmospheric CO2) upon which their position rests.
Then there are the cool people. They claim that the car is actually going in reverse (the planet is cooling, not warming), so we should step hard on the accelerator just to stay in place. But the Earth has a built-in thermometer in the form of sea level, and not only is the sea level rising, it is doing so at an increasing rate. Earth's built-in thermometer tells us that the planet is warming, and fast.
Finally we have the see-you-in-paradise crowd. In their rosy view, we're heading not toward a cliff, but the entrance to a lush tropical paradise. But to accept this premise you have to ignore the fact that, in the time of greenhouse Earth when CO2 levels were higher than today, the tropics were too hot even for the dinosaurs, and this in spite of the fact that the Sun burned 5% cooler then.
Now here's the thing. Every vehicle has a stopping distance and a turning radius, so if we wait too long, we will be unable to stop or even turn in time, and we will go over the cliff. That is why it is imperative that we all become climate realists, and demand that our political leaders become climate realists, too, so that mitigating action can be taken before it is too late.
*The reference here is not to the denialist organization of the same name.