The Indigenous fight for citizenry in the United States has been fraught with hardships and violations. Such history of the struggle of citizenry is sometimes reductionist. Within the context of post World War 1, there is a tendency to negate all Indigenous actions that struggle against the government for their violations and the rights that Indigenous people do have now are due to their actions being subsumed within the systems that oppress them.
Over 12,000 Indigenous people served in WW1: ~6000 volunteers, ~6500 drafted (citizens and non-citizens who waived draft exemption).
While there are a myriad of reasons for why Indigenous people joined the war effort, it would be presumptuous to assume it was out of some sort of United Statsian patriotism. Many of these Native communities sought to fight for the pursuit of civil rights such as recognition of sovereignty, access to citizenship. It was not until 1924, Congress passed the Indian citizenship act, extending citizenship to all Native Americans.
For the naive or the settler historian, it might seem fruitful for the Indigenous to gain such a stride. That there is a possibility to work through the systems to gain sovereignty and liberation. But dying for your oppressor nation is not liberation. Liberation cannot be sought through such ideal. While nominally, the Indigenous person has gained full citizenship, as explained by the Department of the Interior report from 1952 which remarks:
“Today, the American Indian is a full citizen of the United States, such status having been assured him by legislative enactment in 1924.”
Formally, universal citizenship did not end the legal and popular discrimination, nor the infringements of upon tribal sovereignty. Sovereignty cannot be found through the system but outside. Outside through revolutionary and rebellious struggle committed by Indigenous people.