If global warming is real, caused by human activity, and catastrophic for human life then I'd expect the powers that be to act very much differently than they are. Since they don't seem to be acting in a way consistent with being convinced of the dangers of fossil combustion then I feel no need to do so either. Here's a few things I'd like to see from the US Federal government to convince me that CAGW is a real and actual threat.
Lets start with the big consumer of fuel in the federal government, the military. The US Navy wants nuclear powered ships to replace their oil fired ships, they should give them to them. Carriers and subs are already nuclear powered but so should every "mini-carrier", those helicopter landing ships, amphibious attack ships, and other ships that carry helicopters, amphibious landing craft, and command and control ships of similar size and design. The US Coast Guard is in need of some new ice breakers to enable the US Navy and cargo ships to navigate the Northern seas. Last I heard they wanted six ice breakers, two heavy, two medium, and two more of a light, heavy, or medium capacity. As they service Antarctic stations these ships would preferably be as large as possible, carry as much cargo as possible, be as speedy as possible, and be able to travel in tropical waters. Russia has nuclear powered ice breakers but they are stuck in the Arctic due to the risk of over heating when traveling near the equator, the cooling systems need near freezing waters to keep the reactors cool.
The US Navy has been developing a technology that can extract CO2 and hydrogen from seawater and turn that into fuel suitable for their helicopters, jets, and smaller seacraft. This uses nuclear power to drive the process and therefore creates a carbon free hydrocarbon based fuel. If this works for the Navy then it will work for the other uniformed services too.
This also removes much of the incentive to obtain fuel from war torn nations, further removing the need to send troops to far off places.
Then we can move on to non-military consumers of fossil fuels.
One big way we have seen the USA reduce it's carbon output is in the falling price of natural gas. Natural gas produces half the CO2 output per kWh of electricity than that produced by coal. Not an ideal solution but something that requires no government spending and creates a large gain in solving the problem. The federal government could throw open the doors on natural gas exploration, further lowering the price of natural gas and no one would burn coal, simply because NG is cheaper. If it gets cheap enough long enough then we can see gains in conversions of planes, trains, and automobiles to replace petroleum oil.
If this US Navy technology of seawater to jet fuel can be used commercially then there is another avenue to free us from drilling for fossil fuels.
The big way that we can see CO2 emissions go down is growth in the nuclear power industry. So many claims of nuclear power being unsafe are based on old nuclear power plants that are no longer in use. We have not made nuclear reactors like Chernobyl, Fukushima, and Three Mile Island in decades. Even if we did, would not the risk of another nuclear accident pale in comparison to environmental collapse from continued fossil fuel use? Have we not learned how to deal with this nuclear waste since then? As in using waste annihilating nuclear reactors? These things will eat the nuclear waste while producing energy. They also produce life saving medicines for diagnostics and cancer treatments.
So, why hasn't the government done all of this already? Isn't the answer obvious? Because they do not believe their own fear mongering. If they did believe that burning fossil fuels would end us all then they'd do much of what I laid out.
Instead they fund "climate summits" in far away tropical resorts, fly thousands of people there, talk about how much money America needs to give to other nations to pay for they environmental damage that we supposedly did, but no real demands we stop producing the food, medicine, and such that this carbon based economy gives them. These "summits" end up with no binding agreements, a bunch of applause from a press that refuses to ask anything of substance, and everyone goes home, nothing changes, but they promise to do this again so all these government types can get another free vacation.