While the Lakota Sioux certainly have a reasonable basis for complaints against the United States, seceding from the US is probably one of the worst things that they could do.  Having visited the independent "government's" website, it seems to me that they have not taken into account how hard it would be for them to survive as an independent nation.  They are proposing that their residents would not have to pay taxes provided that they renounced their US citizenship.  What I would like to know is how do they intend to pull their people out of poverty with no money? Despite how small the aid the US government has given the Sioux has been, the US will stop any and all aid.  The geography of the Sioux "nation" would force them to become a completely agricultural society with no industrial capacity to speak of and little to now way to export their products to any other nation besides the US, who may or may not be willing to support them by buying their products.  Finally, think of the people that the Sioux will be taking land away from.  These people have their entire lives tied to the land they live on, they are not the kind who will peacefully leave their property when it is assumed by another nation.  While the Lakota Sioux certainly have many reasons to be angry with the US government, a successful secession would be one of the worst things that could happen to them.