While presidents have long had disagreements on national policy, many agreed that unchecked immigration to the United States ultimately hurts Americans and those legal immigrants who have already arrived.

Five presidents, in particular, have famously warned against mass immigration to the United States — despite their differences on a variety of other issues.

Calvin Coolidge

In the early 1920s, President Calvin Coolidge (R) drastically reduced annual legal immigration levels to the United States, stabilizing the nation’s population following decades of record-high immigration.

Coolidge, in a December 1923 address, said immigration levels must not exceed the ability of Americans to absorb new arrivals and that “America must be kept American.”

“American institutions rest solely on good citizenship. They were created by people who had a background of self-government,” Coolidge said:

New arrivals should be limited to our capacity to absorb them into the ranks of good citizenship. America must be kept American. For this I [sic] purpose, it is necessary to continue a policy of restricted immigration. It would be well to make such immigration of a selective nature with some inspection at the source, and based either on a prior census or upon the record of naturalization. Either method would insure the admission of those with the largest capacity and best intention of becoming citizens. I am convinced that our present economic and social conditions warrant a limitation of those to be admitted. We should find additional safety in a law requiring the immediate registration of all aliens. Those who do not want to be partakers of the American spirit ought not to settle in America.

Bill Clinton

Democrat and Republican lawmakers applauded when President Bill Clinton (D), in his 1995 State of the Union address, blasted mass immigration to the United States as a detriment to American citizens who are forced to pick up the tab.

“All Americans … are rightly disturbed by the large numbers of illegal aliens entering our country. The jobs they hold may otherwise be held by citizens or legal immigrants. The public services they use impose burdens on our taxpayers,” Clinton said.

Taking a step even further, in June 1995, Clinton proudly endorsed the recommendations made by the U.S. Commission on Immigration Reform, which was chaired by civil rights icon then-Rep. Barbara Jordan (D-TX).

The commission recommended cutting legal immigration levels in half, admitting about half a million immigrants annually, while carrying out an aggressive assimilation process for new arrivals and driving up deportations of illegal aliens.

Theodore Roosevelt

President Theodore Roosevelt (R) laid out his vision for controlling immigration to the United States in an April 1894 essay titled “True Americanism” in which he argued that assimilation is vital to the foundation of American principles.

Roosevelt wrote:

The mighty tide of immigration to our shores has brought in its train much of good and much of evil; and whether the good or the evil shall predominate depends mainly on whether these newcomers do or do not throw themselves heartily into our national life, cease to be Europeans, and become Americans like the rest of us. More than a third of the people of the Northern States are of foreign birth or parentage. An immense number of them have become completely Americanized, and these stand on exactly the same plane as the descendants of any Puritan, Cavalier, or Knickerbocker among us, and do their full and honorable share of the nation’s work.

But where immigrants, or the sons of immigrants, do not heartily and in good faith throw in their lot with us, but cling to the speech, the customs, the ways of life, and the habits of thought of the Old World which they have left, they thereby harm both themselves and us. If they remain alien elements, unassimilated, and with interests separate from ours, they are mere obstructions to the current of our national life, and, moreover, can get no good from it themselves. In fact, though we ourselves also suffer from their perversity, it is they who really suffer most. It is an immense benefit to the European immigrant to change him into an American citizen. To bear the name of American is to bear the most honorable titles; and whoever does not so believe has no business to bear the name at all, and, if he comes from Europe, the sooner he goes back there the better.

Barack Obama

In his 2006 book “Audacity of Hope,” then-Sen. Barack Obama (D-IL) — who would later win the 2008 presidential election — said illegal and legal immigration must be controlled to not lower the wages of America’s working and lower-middle class.

“The number of immigrants added to the labor force every year is of a magnitude not seen in this country for over a century,” Obama noted in the book, going on to write, “If this huge influx of mostly low-skill [sic] workers provides some benefits to the economy … it also threatens to depress further the wages of blue-collar Americans [and] puts strains on an already overburdened safety net.

Donald Trump

Perhaps most defined by immigration policy, President Donald Trump (R) successfully campaigned in the 2016 presidential election on immigration moratoriums, increased deportations of illegal aliens, building a border wall, abolishment of work visa programs to shore up jobs for Americans, and championed the plight of Angel Families.

In August 2016, Trump issued an address on immigration in Phoenix, Arizona which has helped define the Republican Party.

“The fundamental problem with the immigration system in our country is that it serves the needs of wealthy donors, political activists, and powerful politicians,” Trump said:

Let me tell you who it does not serve. It does not serve you the American people. Doesn’t serve you. When politicians talk about immigration reform, they usually mean the following: amnesty, open borders, lower wages. Immigration reform should mean something else entirely. It should mean improvements to our laws and policies to make life better for American citizens.

If we’re going to make our immigration system work, then we have to be prepared to talk honestly and without fear about these important and very sensitive issues. For instance, we have to listen to the concerns that working people, our forgotten working people, have over the record pace of immigration and its impact on their jobs, wages, housing, schools, tax bills and general living conditions. These are valid concerns expressed by decent and patriotic citizens from all backgrounds, all over. We also have to be honest about the fact that not everyone who seeks to join our country will be able to successfully assimilate. Sometimes it’s just not going to work out. It’s our right, as a sovereign nation, to chose immigrants that we think are the likeliest to thrive and flourish and love us.

John Binder is a reporter for Breitbart News. Email him at jbinder@breitbart.com. Follow him on Twitter here.