No there is not. He makes a clear distinction between Alderaan and a military target. He then asks specifically for the location of the rebel base. If Alderaan was a military target then there is no logical reason for him to make that distinction.
Occam's Razor. Your theory assumes Tarkin considered Alderaan a military target, then assumes that his distinction between Alderaan and a military target is meaningless before assuming that the reason he didn't claim Alderaan was a military target verbally is he didn't feel like debating the point despite him defending Alderaan as a military target being the only way to communicate the idea it is a military target to the audience. Finally you assume he makes the distinction between Alderaan and a military target to avoid being sent to an empty system despite him stating specifically what location he wants a couple of sentences later.
My theory assumes that his distinction between Alderaan and a military target means he did not consider Alderaan a military target. Guess which idea has fewer assumptions.
There's less assumptions here then you would think.
-Alderaan was a MAJOR supporter of the rebellion in logistics and leadership and arguably actual war material .
-Alderaan's government at the highest level was complicit in actively conspiring against and trying to overthrow the Empire.
-The Empire knew of Alderaan was a haven of Rebel activity and Bail Organa had long been on Palpatine's hit list from the Republic Senate days.
Supplying support and infrastructure to an armed group of people trying to destroy your government, has historically = "Military Target"
Tarkin was using an interrogation technique fooling Leia that the Empire didn't know of Alderaan's treason and thus giving her hope that by giving up the Rebel base she had the power to save the planet. She never did. Palpatine dissolving the Imperial Senate and removing Bail Organa from the galactic political stage coupled with destroying a known haven of dissonance was him letting the galaxy know he was taking off the kid gloves.
Lucas may have originally intended Alderaan to be the perfect rebellion-innocent utopia, but over the years the franchise runners have changed that. (Standard disclaimer: Still not saying it was cool to blow it up).