This won't happen unless TN and GA get involved with GA being the key. A new Atlanta stations must come first. But the biggest problem is the geography. The fastest schedule ever operated was about 6 hours for the 285 miles. That's not highway competitive and you can't move mountains without massive investment. More likely are short commuter type runs from both cities into the distant suburbs or maybe Murfreesboro from Nashville and Cartersville from Atlanta.
Now Nashville to Memphis is certainly feasible with good potential stations at both ends and relatively flat for the 225 miles. I suspect rail traffic on CSX is less than on the Atlanta route. Tennessee would no doubt be more interested in paying for an intrastate service than one going to Atlanta. It could of course connect to the CONO.
With how Republican controlled the Tennessee and Georgia legislatures are, as AMAZING as a Nashville-Atlanta Amtrak train would be, I'm not holding my breath it'll be approved. The most I could see being approved in the Atlanta area(and a BIG IF, were the Georgia legislature to somehow approve funding it), is possible new commuter train service along the rail line northwest between Atlanta and Marietta. Maybe if there was enough push by legislators, the train could possibly run at least northwest to Kennesaw, if not further to say like Cartersville? Also it'd be interesting if commuter rail service was ever considered for the areas northeast of Atlanta like north to Norcross, if not possibly further like Buford and Gainesville? Sadly with me remembering I read online that Gwinnett County residents voted down expanding bus service not long ago in a referendum, I'm sadly not holding my breath it will be approved. I really BADLY wish it could be approved, due to how very well I know how horrible traffic issues are in the Atlanta area!
And to a lesser but growing extent, Nashville definitely also suffers from similar traffic issues due to growth in its metro area in recent years. Someone else mentioned the Music City Star commuter train, and yep for sure it'd be great if more than just Nashville to Lebanon service existed. Like say have new commuter rail lines created for service south to Franklin, southeast to Murfreesboro, northeast to Gallatin, and northwest to Clarksville. I do worry there'd be enough NIMBY voters, to at least some commuter rail proposals from seeing the light of day sadly. I.e. I worry that a line to Clarksville wouldn't get approved, but maybe for all I know Williamson County voters(near Franklin) or Rutherford County voters(near Murfreesboro) would approve new commuter rail proposals? Also it'd be great if more weekday service ran(NOT just during rush hours), and ditto with creating regular Saturday and Sunday service.
Not saying it isn't impossible for new train service to be created, as evidenced by the fact that Mobile, AL's city council approved funding for a regional Amtrak Mobile-New Orleans train that'll enter service sometime in the next few years. It is sad Alabama's governor(Kay Ivey) rejected signing off on funding for that train, but doesn't surprise me she acted like a typical GOPer in sadly rejecting such funding.
