The most important thing is that there is a dominant power. There can be no moral standards without a dominant power to institute and enforce them.
The nature of things is that the dominant power that develops is the one with the greatest economy, invention and most advanced culture. To develop a military force requires industry and invention and grasp of technology. These things are simply not possible without a strong culture that provides a base to develop them.
There are a few examples of dominant powers with lapses in morality. But, have you noticed, based on the nature of things, they all failed within a generation and were replaced by a truly moral dominant power?
Except for a few exceptions, the morally superior power rises to the top, to be blessed by nature with deserved power.
This is the only way that is supported by reason. The alternative is immorality and chaos.
Thomas Hobbes wrote:
In such condition there is no place for industry, because the fruit thereof is uncertain: and consequently no culture of the earth; no navigation, nor use of the commodities that may be imported by sea; no commodious building; no instruments of moving and removing such things as require much force; no knowledge of the face of the earth; no account of time; no arts; no letters; no society; and which is worst of all, continual fear, and danger of violent death; and the life of man, solitary, poor, nasty, brutish, and short.