Sentence:  The action of the Commission in allowing or denying any <WSD>claim</WSD> under this title shall be final and conclusive on all questions of law and fact and not subject to review by the Secretary of State or any other official , department , agency , or establishment of the United States or by any court by mandamus or otherwise . 
Meaning of the word marked with <WSD> tags:  an assertion of a right (as to money or property)