I'm in awe of this Icelandic volcano's effect on European airline travel. Just think of how fscked Europe would be if they did not have a great rail system. Not that the trains can accommodate all the stranded air passengers but the situation would be vastly worse without them.
If you were a jingoistic, teabagger type you might say, "we have nothing to learn from the Europeans." Since I'm not one of the aforementioned knownothings I'll say, "we need a high speed rail system connecting the twenty largest cities in the U.S. and screw the mission to Mars." The rail system would employ vastly more people (of all skill levels) than a Mars mission and it's actually needed.
Let this rail system be a mix of public and private operators for all I care as long as it works. We'll be especially glad we built it when one of our own volcanoes erupts.