"But you neglect in your response the requirement of the Maglev launcher being constructed in various locations. You first have to GET to that rare capital built up Maglev launch location to get the benefit of the fast launch. Far better to take off from most any airfield and spend a few tens of minutes reaching altitude."

I'm not suggesting that Virgin galactic build a Mag Lev and any other suborbital space company do this. They should plan to take off from a airfield.

What I'm suggesting is some other party might work with the State of Virginia to build the mag lev- preferable a party which has some experience or association with Mag Lev trains.

Another aspect of this is that such a Mag Lev track could similar to race cars to automobile makers. Such a track would be pushing the limit in terms of speed and acceleration- and if at higher elevation, higher operation in an environment with less air density.

So, the track would built at the current state of the art, and over the years have an incentive to make the track go faster. But if you only make the track go at 300-400 mph, that's fine- do that and make a profit. What would good is if one has future plans, say 20 years after it's built, to expand and improve the track [perhaps to include enclosing the track and having a vacuum so that even higher speeds are possible.

Virginia interest can be the opposite of a sub-orbital rocket maker- they could want narrow where the sub-orbital vehicle launch from. And do so by having a advantage of launching from the Mag Lev track in their state.
The state of Virginia doesn't need to make the sub-orbital it just has to make a good place to use sub-orbital vehicles.

Though there is a problem, Virginia doesn't seem to have much in terms of elevation:
http://www.geonames.org/US/VA/highest-mountains-in-virginia.html
The highest mountain being 1,744 m and 10th highest is 1,503 m and all 10 are in one general area- which doesn't look that good.
Hmm. There is deep water near Wallops Island launch site- about 80 mile out and 1000' deep
http://www.nrdc.org/water/oceans/priority/canyon_map.html

And, there isn't much in terms of elevation anywhere on East coast of America:
"Mount Mitchell in North Carolina, 6,688 feet, and Mount Washington, in New Hampshire, 6,203 feet, are the highest peaks."
http://chestofbooks.com/reference/The-New-Student-s-Reference-Work-Vol1/pp0075.html

So, somewhere around 4 to 5000' is about the best one could hope to find in Virginia or anywhere on east coast of America.