The cause of global warming is well known - excess carbon dioxide in the atmosphere due to the use of fossil fuels for energy production both in large-scale power plants and small-scale vehicles. At the current moment it seems as though the global addiction to fossil fuels is and was unavoidable because of problems with renewable energy sources: hydro-electric and geothermal energy are geography dependent, wind and solar energy is not consistent enough to be viable without huge capacitors/batteries to store the produced energy or fossil-fuel backups. However, this impasse is entirely a product of the public's fear of nuclear power.
Nuclear power was the only way we could have avoided climate change. The technology was available in the 1960s leaving at least 50 years to make the conversion before climate change became a problem. When scientists started ringing the alarm bells about global warming in the 1980s already 16-17% of global electricity was being produced from nuclear power-plants. Nuclear power is not dependent on geography, produces steady output and is compatible with our centralized energy production model. In several regions nuclear power already supplies over half the electricity demand. Even in Germany, where nuclear power has struggled and renewable energy has seen massive growth, nuclear power supplies more total electricity than renewables (wind, solar, biomass, hydro). That was until the recent closures of nuclear power stations - a pledge which may cause Germany to miss their GHG emission targets.
Nuclear energy was developed and expanded from the 1950s to the 1970s going from 0% to over 15% of global energy production in as many years. If that rate of expansion had continued we could have been in a world where 50% of global energy production was obtained from nuclear power which is nearly carbon neutral (reducing CO2 emissions by ~2,500 million metric tons).
Beyond electricity production, nuclear power is suitable for medium-scale projects such as submarines meaning is possible the technology could be used for international cargo ships which used the dirtiest, most polluting fuel of all. Shipping currently emits roughly double the CO2 of the aviation industry, meaning the substitution of nuclear power could save another 500 million tonnes.
The question is why haven't/won't we make the move to nuclear? Nuclear power development started dying off in the 1970s as the public turned against the technology. The 1970s and 1980s saw many anti-nuclear protests, the formation of green-parties, and the foundation of Greenpeace. But where did this opposition come from? In the 1950s there was a sense of optimism and excitement about nuclear technology - surprising given the devastation caused by the nuclear strikes on Hiroshima and Nagasaki - but I suppose it was spun as the hero who won the WWII in the West. It certainly wasn't triggered by a nuclear accident because the first major meltdown wasn't until 1979 at Three Mile Island.
Using Greenpeace as a case study, I suggest the anti-nuclear movement was born of the Cold War, the illegitimate child of various anti-nuclear weapons movements. The name should give you the first clue 'Greenpeace', its first mission was to stop the testing of nuclear weapons in sensitive habitats. Now 50 years later they still advocate for nuclear disarmament but spend much more of their time/efforts opposing the development of nuclear power. The link is clear, most arguments against nuclear weapons focus on the dangers of radiation and nuclear power also uses radiation.
Fear of radiation is pervasive in our current culture - it is even taught in schools. History classes routinely teach pupils about the after effects of the nuclear detonation at Hiroshima. English classes often cover books written during the Cold War warning of nuclear apocalypse. And who hasn't heard about the Chernobyl disaster, despite the fact that it occurred before I was born and will kill fewer people than 1/10 of those who die of medical mistakes in the USA each year.
The fear of radiation is so strong and the understanding of radiation is so low that Californians were exposing themselves to more radiation by taking iodine pills than they were from the Fukushima disaster they were trying to protect themselves from. Similarly in the mid-2000s there was a public health-scare over the radiation emitted from mobile-phones despite that radiation being only a tiny fraction of the radiation people receive from the Sun on a daily basis and being the same type of radiation they happy use to quickly heat their food. It is this irrational fear of all things branded as 'radiation' that is slowing and in some countries completely preventing the construction of new nuclear power-plants which will be necessary if we are ever to achieve a zero-carbon economy.