Article 13
The object of this instrument being to advance the interests of the Ioway people, it is agreed, if it prove insufficient, from causes which cannot now be foreseen, to effect these ends, that the President may, by and with the advice and consent of the Senate, adopt such policy in the management of their affairs, as, in his judgment, may be most beneficial to them; or Congress may hereafter make such provision by law as experience shall prove to be necessary.