2. The U.S. frowns upon slavery.
The cost of producing the embryos may be minor, but implantation is costly. It is unlikely that you will find sufficient women to voluntarily pay for the procedure, carry to term, and raise to the age of majority. Even with subsidies, I don't suspect you will have lines around the block signing up to be axlotl tanks.
If there were a sufficiently motivated or desperate population, how many of the resultant perfect troops would be motivated to serve? How many as a result of environment would remain medically, educationally, and morally qualified?
The return on investment without the employment of compulsory service doesn't make sense.
Eliminate the development phases and we would then have an age limit to deal with. Overcoming that, the educational requirements would still take around 10 years (I think I saw somewhere that 8th grade was the bare minimum requirement for enlistment)
If we somehow managed to create a factory for fully developed educationally qualified humans, you might be able to provide and illusion of choice when it comes to service. If the alternative is to drop them in the civilian market with absolutely no support structure, it isn't much of a choice at all.
If they are unable to make a qualified decision, the service is at best coercive if not compulsory.
The only outcomes I can see are that it will be ineffectual, or an anathema to a free society.
Blade Runner comes to mind.
A force of "perfect" service members (with free will and guns, no less), bred for conflict by a civilization that can create clone after clone of the same person, would soon realize they are death-dealing slaves, and rebel.
We would repress the human desire for freedom to keep from fighting our own wars. And that’s another thing. We would sanitize the war experience by sending in clones to do the work, and lose the horrific perception of armed conflict. War would never end, because it would never have to.
And how would we treat these clones if they integrated into our society of “natural born” humans? Veterans have a hard enough time, now we have vets from a test tube that no nothing but conflict. Nevermind their vet status, would we even treat them as equal humans?