The union was known for its militant measures in dealing with opposing forces, and firm in its opposition to the politics that existed in the country during the Cold War.
Travis eventually left the party to comply with specifications of the Taft-Hartley Act, but his activities were heavily scrutinized by Senator Joseph McCarthy and his investigators.
[3] By the 1950s, the International Union of Mine, Mill and Smelter Workers had achieved establishment of approximately 300 locals, with about 37,000 total members in the United States and Canada.
[7] These powerful measures created an atmosphere of fear, and Mine Mill's leaders' ties to the communist beliefs caused debate inside and outside of the union.
[8] Mine Mill leaders in the United States (Philip Murray) and Canada (Aaron Mosher) were both conservatives with a leaning to communist beliefs.
[12] The CIO and the Steelworkers groups, who expected to benefit from an exodus, failed to recognize the loyalty of the western mine workers who did not respond to the propaganda that had been sent their way.
Leaders of the Mine Mill Union opposed signing the affidavits based on First Amendment grounds, but eventually they complied.
Secretary/Treasurer Maurice Travice publicly renounced his association with the Communist Party, but several of Mine Mill leaders were convicted of falsifying their Taft-Hartley affidavits.
[16] James L. Daugherty, the union's chief negotiator, refused to sign an affidavit, and he appealed to the president to stop the indictments against communist sympathizers.
[17] Distrust was in the atmosphere, and the CIO supported several articles, flyers and radio broadcasts aimed to weaken the Mine Mill's position with its members in the 1940s and 1950s.
Author Pierre Berton reported that Mine Mill smelter workers were producing a dangerous component used in the making of bombs, under the direction of Harvey Murphy.
[19] The Mine Mill leaders became involved in organizing a series of annual concerts that took place between 1952 and 1955 on the United States/Canada border at Vancouver.
He ignored advice to edit his public statements, praising the Soviets for their achievements and criticizing President Harry Truman for involving the United States in the Korean War.
Although Robeson had a large following in Canada, the American government limited his ability to reach his fans by pulling his passport in 1950, restricting his travel.
[22] Robeson's outspoken ways angered anti-communists in both the United States and Canada, and in February 1952 authorities prevented him from appearing in person at a conference sponsored by the Mine Mill leaders.
When Mary Orlich publicly attacked the Mine Mill's communist ties in her auxiliary presidential platform in 1947, the union was powerless to stop her.
The ongoing communist leanings of the Mine Mill leaders became unfavorable, and community opposition factored into changes in the members’ positions.