President Harry Truman recognized the moral obligation that the United States and other nations had to help these persons. In a statement he wrote on December 22, 1945, he said:
"The great difficulty is that so many of these persons have no homes to which they may return. The immensity of the problem of displaced persons and refugees is almost beyond comprehension. A number of countries in Europe, including Switzerland, Sweden, France, and England, are working toward its solution. The United States shares the responsibility to relieve the suffering. To the extent that our present immigration laws permit, everything possible should be done at once to facilitate the entrance of some of these displaced persons and refugees into the United States."
With Truman's support, the United States helped to fund temporary camps, and admitted large numbers as permanent residents as immigrants. Truman strongly supported the program, and obtained ample funding from Congress for the Displaced Persons Act of 1948. This law authorized the admission into the United States of certain European displaced persons for permanent residence. Truman strongly supported the program, and obtained funding from Congress. He also supported the admission of Jewish refugees in Palestine and Israel.
After the end of World War II, immigration immediately increased under the official national origins quota system as refugees from war torn Europe began immigrating to the U.S. After the war, there were more jobs available, as most women employed during the war returned to their homes. From 1941 to 1950, 1,035,000 people immigrated to the U.S., including 226,000 from Germany, 139,000 from the UK, and 57,000 from Italy. When the Displaced Persons Act of 1948 was passed, some 200,000 Europeans and 17,000 orphans displaced by the war were initially allowed to immigrate, in addition to the 1924 quotas. The first Displaced Persons Act on June 25, 1948 allowed entry for 200,000 such persons. A second Displaced Persons Act was passed on June 16, 1950, allowing entry for another 200,000. This quota required sponsorship for all immigrants. Much of the humanitarian effort was undertaken by charitable organizations, such as the Lutheran World Federation as well as other ethnic groups. Along with an additional quota of 200,000 granted in 1953 and more in succeeding years, a total of nearly 600,000 refugees were allowed into the country outside the quota system, second only to Israel's 650,000.
The Truman administration helped create a new category of refugee, the "escapee" at the 1951 Geneva Convention Relating to the Status of Refugees. The American Escapee Program began in 1952 to help the flight and relocation of political refugees from communism in Eastern Europe.
In 1945, the War Brides Act allowed foreign-born wives of U.S. citizens who had served in the U.S. Armed Forces to immigrate to the United States. In 1946, the law was extended to include the fiancés of American soldiers.
In 1952, the McCarran Walter Immigration Act passed over Truman's veto. It kept the old 1924 quota system but added many new opportunities for immigration from Europe and elsewhere. In practice two-thirds of the new arrivals entered outside the old quota system. In his veto message, Truman wrote:
The idea behind this discriminatory policy was, to put it baldly, that Americans with English or Irish names were better people and better citizens than Americans with Italian or Greek or Polish names. It was thought that people of West European origin made better citizens than Rumanians or Yugoslavs or Ukrainians or Hungarians or Baits or Austrians. Such a concept is utterly unworthy of our traditions and our ideals. It violates the great political doctrine of the Declaration of Independence that "all men are created equal." It denies the humanitarian creed inscribed beneath the Statue of Liberty proclaiming to all nations, "Give me your tired, your poor, your huddled masses yearning to breathe free." It repudiates our basic religious concepts, our belief in the brotherhood of man, and in the words of St. Paul that "there is neither Jew nor Greek, there is neither bond nor free .... for ye are all one in Christ Jesus."
Truman also struggled with the problem of migrant farm workers — both legal and illegal. On June 3, 1950, he set up a Presidential Commission on Migratory Labor. The commission was tasked with investigating "the extent of illegal migration of foreign workers into the United States" and whether laws could be "strengthened and improved to eliminate such illegal migration." The commission ultimately recommended that the country should rely primarily on domestic farm workers, not immigrants, to perform farm labor. On July 13, 1951, Truman approved legislation to facilitate the employment of legal migrants to harvest U.S. crops, but also expressed a desire to reduce illegal immigration from Mexico and said additional measures were needed. He said "These people are coming to our country in phenomenal numbers – and at an increasing rate. Everyone suffers from the presence of these illegal immigrants in the community."
Truman signed legislation concerning legal guest workers flowing across the border to harvest U.S. crops. The new legislation established reception centers to house temporarily legal immigrants from Mexico while the government found employment for them. Truman said in signing it, "We must make sure that contract wages will in fact be paid, that transportation within this country and adequate reception centers for Mexican workers will in fact be provided." Truman said that it was necessary that the U.S. government "stand behind all contracts and guarantee performance in the future, if any more Mexican citizens are to be legally recruited for work in the United States."
During Truman's presidency more than 127,000 illegal Mexican aliens were formally deported and more than 3.2 million left voluntarily rather than face deportation. Truman asked Congress for stricter sanctions against employers who harbor illegal aliens, but Congress did not pass the legislation Truman wanted.