Prevention of what? Could be, may be, might be injury? Or not? Hardly the kind of standing to build a case on.
The standing issue is simple. If the Lt. is not a member in good standing of a recognized armed force, following legal orders, (the Geneva standards) and he kills someone in an offensive operation, he could be considered a murderer.
For example, If he was ordered to patrol in Iraq, and the US rules of engagement allowed him to engage (kill) anyone carrying a rifle (even though they were not making any hostile move towards him) then he is protected as a member of the US Army.
However, if it could be established that he was not following a legally issued order, (because the CINC was not legally the President,) then he places himself in jeopardy of a murder accusation or other prosecution by the Hague, host country or other self-serving do-gooders.
(Please note that I am not saying a “legal order” but rather “legally issued order.’” Two very different things)
New and WaterBoy attacked the LEGALITY OF THE ORDERS THEMSELVES, not the LEGAL STANDING (AUTHORITY) OF THE ULTIMATE ISSUER.
Issue that would be before the court is: Is Obama POTUS... or as I now call him, POTPOPOTUS; "Pretender Occupying The Position Of President Of The United States."
Lt. certainly has the standing to ask a US court to clarify the issue of the legality of THE ISSUE OF his orders, and that certainly depends on Obama's citizenship status!
It's far from far-fetched..... and it's that simple, and that serious.