Trains have been proven to be able to go at least 375mph [0]. That would make NYC->SF take 6.9 hours to travel the 4162 km. The current average flight time from NYC to SF is 6.7 hours.
So, it's at least technically possible.
China is doing R&D on a partial-vacuum train (basically Musk's hyperloop thing) with a target of 1,243 mph[1]. That's probably a pipe dream, but worth mentioning nonetheless.
> The government should of [sic] bailed out Spirit instead.
I'd be okay with this if all the taxpayers were granted equal shares that their collective money could have purchased at an imputed no-bailout price.
0: L0 Series SCMaglev
1: T-Flight train