Beginning in the early 1930s, the United States federal government was infiltrated at the highest levels by Soviet Communist agents and other "fellow travelers."
M. Stanton Evans and Herbert Romerstein in the following book document in great length USSR infiltration into the USA federal government, as well as the mass media, universities, unions, etc. This included a large number of communist sympathizers as well as outright Soviet agents. A few examples: Harry Dexter White (Treasury Department), Alger Hiss (State Department), Harry Hopkins (White House), and Lauchlin Currie (White House).
Stalin's Secret Agents: The Subversion of Roosevelt's Government
HTML: https://web.archive.org/web/100/http:// ... gents-FDR/ or https://archive.fo/uHtdy
TXT: https://archive.fo/xXV3g or http://web.archive.org/web/100/https:// ... g/ymGwX2nw
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The claim is that an international communist conspiracy took over the US government under US President FDR. Soviet agents operated at the highest levels of the US federal government, formulating policy, engaging in espionage, and otherwise advancing their diabolical Communist agenda at the behest of Moscow and to the detriment of the American people. Evans and Romerstein summarize this period of history in the final chapter of their book (pages 254-255):
First and foremost, there can no longer be any serious question, at least among serious people, that Communist and pro-Soviet penetration of the American government was extensive, involving many hundreds of suspects, and that by the era of World War II and early stages of the Cold War reached up to significant levels. The now available documentation to this effect is massive.
Second, the infiltrators in numerous instances were able to wield important leverage on US policy overseas in the war years and the early Cold War. This was achieved by pro-Soviet operatives who variously controlled the flow of official information, propagandized their superiors in favor of pro-Red causes, or in some cases actually made or guided key decisions. By such leverage the likes of Lauchlin Currie, Harry White, and Solomon Adler (or in Great Britain, the Communist James Klugman) were able to steer the policies of the West in favor of pro-Communist interests.
Third, pro-Red penetration and the resulting policy damage occurred because Soviet agents preyed on the credulity of officials who were ignorant of Communist methods and apparently had no interest in learning. A striking pattern in the record is the extent to which sophisticated Soviet agents attached themselves to naive US officials who were highly susceptible to disinformation. The classic cases were White with Henry Morgenthau at the Treasury and Alger Hiss with Stettinius at State, but there were many similar match-ups elsewhere during the course of the Cold War struggle.
The net effect of these converging factors was a series of free-world retreats, as pro-Communist forces triumphed in a host of European countries during the earliest stages of the Cold War, followed by the fall of China to Communism a few years later. These events would be a prelude to Marxist conquests elsewhere, in places as disparate as Indochina; the Latin American states of Cuba and Nicaragua; African nations, including Zimbabwe and Angola; and numerous other cases of like nature.
It's significant that these pro-Red victories were in the usual instance achieved not by conventional armies marching past national borders, but by the actions of subversive elements inside the target nations, prompted and aided by outside Communist powers and with frequent assistance from forces in the United States or other Western nations.
David Martin has reviewed the book here:
Stalin’s Secret Agents: The Subversion of Roosevelt’s Government -- A review by David Martin
https://web.archive.org/web/20130204222 ... 130201.htm or https://archive.fo/0oKXf
Miguel Faria of Hacienda Publishing has also reviewed it:
Roosevelt and Stalin — The Subversion of FDR's Government by Communist Traitors and Fellow Travelers
http://archive.fo/JCKFL or https://web.archive.org/web/20140430145 ... -travelers
Roosevelt's Road To War
The Soviet Union Conspired to Foment World War II and Infiltrate the U.S. Government
Collusion: Franklin Roosevelt, British Intelligence, and the Secret Campaign to Push the US Into War
President Franklin D. Roosevelt's Jewish Cabal
Sources on Jews and Communism