By your own link all light duty vehicles make up a mere 17% of emissions.
Also if you track down the original report that pie chart is drawn from, you’ll find that is only considering direct fossil fuel combustion. Consider all sources and it drops down to 12%.
ALL consumer cars everywhere, for every purpose, amounts to 12% of emissions. Commuting is a smaller fraction of that. I stand by my claim.
How is 17% emissions a small amount? It's as much as our agricultural and commercial emissions combined and 1% more than our residential and commercial emissions combined. It's more than the the emissions of all airline travel. Only industrial and electricity related emissions are more. What other category would you pick to lean up on?
There are other ways CO2 or other greenhouse gasses are emitted besides burning fossil fuels. Examples include outgassing from construction (e.g. concrete), metal refineries, and livestock.
According to [1], the US had net Greenhouse Gas emissions of 6558.3 MMT CO2 Eq, of which transportation CO2 energy emissions took 1817.2 MMT CO2 Eq, of which 58% was due to light-duty vehicles. That means 16% of total emissions are due to light-duty vehicles, not 12% as you say, and only 1% off the 17% listed above.
So then I pose the question again, which set of emissions would you cut? The only other categories that pollute more is industry or electric generation. Which would you cut and why would you rather cut that than the emissions from cars?
Also if you track down the original report that pie chart is drawn from, you’ll find that is only considering direct fossil fuel combustion. Consider all sources and it drops down to 12%.
ALL consumer cars everywhere, for every purpose, amounts to 12% of emissions. Commuting is a smaller fraction of that. I stand by my claim.