As others have commented, $14.5 trillion USD (even with inflation) is nothing compared to the US's current outgoings. What I _never_ see costed is the other side - what negative cost will the climate policies have on GDP? I imagine that number to be far greater. For example: Great, you increased fuel tax and got less people driving. Now people can't get to work, deliveries are now too costly, the cost of living incre…
You're not supposed to say it out loud when you're concern trolling. We've had the other side non stop from every politician and all media for decades. Even the 'left' politicians only do the bare minimum most watered down measures after decades of public pressure and ironclad science and not even that if there's a remote chance it could hurt their donors.
Solar is cheaper than any other option after ten or twenty years of serious investment. Initiating the cost drop has been an option for at least fifty and possibly 100 (as the first commercial PV panels were a technology with good cost efficiency and 5% energy efficiency and were produced decades before the photoelectric effect was discovered -- the creator thought they were thermoelectric initially) years simply by not actively propping up fossil fuel interests at immense cost and instead putting a fraction of that money into renewables.
Cars are the single biggest dead weight loss in any economy by orders of magnitude. Families are spending upwards of 30% of their income and a quarter to half of their productive hours on being able to participate in cities or towns that were intentionally demolished and rebuilt to make them unlivable without one at immense cost. Building walkable towns, trains, and density in place of cars reduces commute times, reduces deaths by hundreds of thousands per year and avoids millions of injuries and illnesses in a country the size of the US.
Without enforcing car ownership, land can be used much more effectively and housing can be far cheaper without dedicating more of a town's land to the car than the residents.
Then there are the trillions spent on destabilizing and invading countries with fossil fuel reserves to ensure they will sell it for a pittance only in USD and not give their workers livable conditions.
Insulation (and sharing 1-3 walls with your neighbors) is an unmitigated benefit to everyone, and all it would have needed is minor policy change.