But the prospects for a victory by Kolchak soon faded and the Whites in Siberia revealed themselves to be a lost cause. The decision to remove the US troops was made late in 1919 and General Graves, with the last of his staff, departed from Vladivostok on 1 April 1920. In all, 174 American soldiers were killed during the invasion of the Soviet Union.
Interestingly, pressure to withdraw the US troops from Siberia came from fed-up soldiers and home-front opinion opposing the continued deployment of military units abroad long after the conclusion of the war in Europe. It is notable that during a Congressional debate on the Russian intervention one Senator read excerpts from the letters of American soldiers to support the case for bringing them home.
https://consortiumnews.com/2018/07/18/when-the-u-s-invaded-russia/
