Brightline is not HSR. It is effectively the same as Amtrak regional. It *is* being done primarily with private money by a spinoff of FEC, though there have been many efforts by adjoining property owners and counties (still going on, actually) to stop it.

The cars and locomotives come from the same places as the ones being build for the state that run their own regional trains. The cars CA has bought new over the years - the Cal Cars/Surfliner cars - are designed for use up to 125 mph on suitable track. Amtrak diesels are theoretically capable of 110-125 depending on model, and the new ones being bought for commuters and regional trains are all capable of 125. So FL is getting what the Surfliner could be with some work (and bypass of a couple of tight spots like San Clemente). Not HSR, but "higher" speed rail that, even with some stops, is competitive with driving, and even short-hop air after you allow for security and airport access time.

Finally, I think the "government money pit" Tri-Rail commuter operation has done a lot to make FL people interested in rail. It works, within its remit. It loses money, as all commuter trains to, but overall return seems to be par or better for the business. But it's there, and people see it, so the latent market is there for Brightline. I wish them luck and good business. The Governor should shut up, though, before he makes even more a fool of himself.