I welcome the genetic modification revolution in humans with open arms. I'm not optimistic, however, that great government regulation is going to accomplish what we want it to accomplish. Governments, especially the US government, is reluctant to even pass any major regulatory policy on automation, and AI, recognizing that in reality, they will be only stifling themselves, as other, somewhat hostile nations will continue to pursue the technology we are denying ourselves. Similarly, I doubt it would be able to form the kind of regulatory policy on genetic engineering that would stifle it self when other nations will have no such regulatory policy.
One can make the case that there ought to be a global convention on this, but if we're going to be realistic and objective, international laws are only as strong as their enforcement mechanisms, and many countries go to incredible lengths to conceal what they are forbidden to do. If the only enforcement mechanism right now is a single super power i.e. the US, we have to ask ourselves the question if the US is prepared to go to war with another nation if that nation is violating the international regulatory policy of genetic modification.
I do not have much fear in the Chinese creating super soldiers, or any nation doing it. Already the future of warfare is going to be AI driven, and practically autonomous. No matter how genetically strong your super soldier is, an AI driven drone can still put a bullet into their gut. And besides, the Chinese have a serious demographic nightmare that is their biggest Achilles heel in their military power: the effects of the one-child policy. Up until probably a few months ago China did not have any kind of social security pension system. The Chinese pension system is entirely familial, you have a child, that child takes care of you in your old age. The Chinese even made it a legal requirement for the young to take care of their elderly. But because of the one-child policy, many of these elderly are entirely reliant on their one child to take care of them. Imagine, then, a large scale war with the Chinese, who's infantry is composed of largely children that have no siblings. Every single one of their soldiers dead means that their parents' retirement is put into jeopardy. It also means that the parents will lose their only child, their only way of passing on the most basic biological function. Any major war with large scale casualties then would create so much internal political problems that the Chinese are effectively incapable of long-term casualty attrition. Anyway, I digress.
The best one can do is strive to keep the following two conditions going forward:
1) Genetic Modification should be, at all times, completely optional. Any coercive measures by the state (any state) to genetically modify a human being should be resisted at all costs, even if the demands may be ultimately good for the person. In the US this is far easier to accomplish because we already have legal system that forbids the government to compel a lot of things in it's citizenry. This gives the state too much power in creating it's own ideal citizen.
2) Genetic Modification should be as widely accessible as possible, to the largest segment of society. Any laws that forbid one set of people to engage in this while allowing another should be resisted. Again this is far easier in the US because of existing discriminatory laws.
Once the proverbial Pandora's box is open (let's be real, it's been open for centuries with livestock breeding, and selective breeding by nobility), the best way to handle it is to expand accessibility. We've seen time and time again what moral prohibitions does to a society, whether it is drugs, alcohol, prostitution, pornography. It always goes underground, it always fuels the criminal underworld, it always creates an unnecessary danger.