Interpretation of the idiom "hold our own" in a speech to Congress in the 19th century

The Nez Perce was a Native American tribe living in Oregon. They engaged in a war with the United States in 1877 and were defeated. The surviving members of the tribe were relocated to Idaho. In less than two years on the reservation, many of them either fled or died. Chief Joseph went to Washington D.C. in 1879 to plead for another home and fair treatment for his people under U.S. law.

I do not understand his intent of the phrase "hold our own" in the following quote.

I see men of my own race treated as outlaws and driven from country to country, or shot down like animals. I know that my race must change. We cannot hold our own with the white men as we are. We only ask an even chance to live as other men live. We ask to be recognized as men. We ask that the same law shall work alike on all men. If an Indian breaks the law, punish him by the law. If a white man breaks the law, punish him also.

Every idiom dictionary that I have consulted has stated that "hold one's own" means to be competent in a particular endeavor. So, it seems to me that Chief Joseph is saying that due to his tribe's surrender, they must submit to U.S. laws, and he is only asking that his people be treated fairly under U.S. law.

Based on a historians interpretation of his speech, though, the intent of this idiom was to concede that his people had been barbaric on the reservation due to a sense of gross injustice. Chief Joseph had written previously in this same speech

If you tie a horse to a stake, do you expect he will grow fat? If you pen an Indian up on a small spot of earth and compel him to stay there, he will not be contented nor will he grow and prosper.

Unless this quote immediately preceded the quote containing the idiom "hold our own," I don't know how this can be interpreted as "abiding by U.S. laws."

For further clarification, the speech is easily found on the Internet.

Solution 1:

hold one's own

PHRASE
Retain a position of strength in a challenging situation.

I can hold my own in a fight Lexico

Chief Joseph is speaking about surviving and retaining an identity ("hold our own" and, in the other passage, "grow and prosper") while recognizing the need to change and submit to the laws of White men. His plea is that this can happen only if his people are treated fairly under the law.

Holding our own doesn't have the same meaning here as it would if said during the war (in which case it would be interpreted as defending themselves adequately, as in the above I can hold my own in a fight). Instead, after surrender and in light of the peacetime casualties the Chief mentions, the meaning of the phrase changes to keep up enough strength to stay alive and maintain an identity.

For the same reason I believe that we must after this war continue to develop our own national resources.
...
If we can but acquire a more scientific outlook and apply in a scientific manner the principle of good estate management of our resources, we can I believe, hold our own against any fair competition. British Offical Statements, Vol. 3 p. 129 (1942)

The new and unprecedented increase in tonnage is a reminder to us that we achieved our old station by building ships of superior speed, carrying capacity, and labor-saving devices. To gain or hold our own after the war will challenge our builders, while it already puts upon our legislators the necessity of repealing laws that increase labor-costs. "How Our Merchant Marine Has Grown," The Literary Digest, Vol. 51, Part 1, p. 565 (1915)

We might say that the post-war meaning refers to a "fair fight" in peacetime.