According to this compelling article, a significant portion of cargo ships could be electrified.
You got some sources for that claim, cause transportation accounts for 28% of u.s. ghg emissions and 57% of that is light duty vehicles, only 3% is ships and boats. So if we delete every car emissions, at least in the u.s. , would go down by 15%, not enormous but also not a drop in the bucket.
I’m all for the other solutions you mentioned, besides nuking China, but we can’t pretend like meat consumption and car use aren’t large factors in climate change that we’ll have to address.