To be a little more serious, LB is a perennial problem for the U.S. (and for most teams). Add to that a requirement that this player be able to defend like a CB while sometimes also defending in space, and it's even more limiting. Players who figure as potential LBs for us - Villafana, Robinson, even F. Johnson, are not this kind of player.
The person to look for would be a left footed CB who has enough skill to play out wide and hit a good pass. What I wouldn't give for Alex Callens, to be honest. Not sure who else on the national team can fit that bill. Besler and Brooks are left footed, for what it's worth.