They will go after it as an illegally exported munition.   This is what they went after Phil Zimmermann for with his Pretty Good Privacy (PGP) encryption program which he posted online years ago.  Zimmermann then published the source code for PGP in a book via MIT Publishing and said 'First Amendment.' 

They will have a problem with prosecuting this too:  A six shot, soon to wear out .38 caliber handgun represents no threat to national security and a judge may not see the law's applicability.  Still they will wail "It can pass through metal detectors your honor!"  But as many schematics as were downloaded worldwide--like PGP--the cat is out of the bag---bite me.

When any government, or any church for that matter, undertakes to say to its subjects, "This you may not read, this you must not see, this you are forbidden to know," the end result is tyranny and oppression, no matter how holy the motives. Mighty little force is needed to control a man whose mind has been hoodwinked; contrariwise, no amount of force can control a free man, a man whose mind is free. No, not the rack, not fission bombs, not anything — you can't conquer a free man; the most you can do is kill him Robert A. Heinlein (1940)