Trump is not the first president to deploy the National Guard to the U.S.-Mexico border

William Cummings | USA TODAY

Show Caption Hide Caption DHS Sec: 'As many as we need' troops to border The Trump administration hasn't determined how many troops it will seek to have deployed to the U.S.-Mexico border. Homeland Security Secretary Kirstjen Nielsen says: "We're going to be sending as many troops as we need." (April 5)

President Trump is taking a lot of heat for his decision to deploy the National Guard to America's southern border, but he is repeating a move made by many of his predecessors.

Former presidents, including Barack Obama, George W. Bush, George H.W. Bush, Woodrow Wilson and William Howard Taft, all issued orders similar to those Trump made in a proclamation Wednesday. In 1954, President Eisenhower's attorney general requested the Army assist the border patrol during a major sweep for undocumented immigrants, but his request was denied.

Here is a look at other times the U.S. deployed — and in one case attempted to deploy — troops to the border.

Mexican-American War

More than a border operation, the 1846-48 Mexican-American War began over tensions related to the U.S. annexation of Mexico. And it led to a full-scale U.S. invasion, that ended with American soldiers seizing control of Mexico City.

More than 13,000 American and 10,000 Mexican soldiers died in the war, and estimates of Mexican civilian deaths run as high as 25,000. As a result of the war, the U.S. took control of the territory that would become Arizona, California, New Mexico, Nevada, and Utah, as well as parts of Wyoming, Colorado and Oklahoma.

Mexican Revolution

From the start of the tumultuous Mexican Revolution in 1910 to its conclusion in 1920, the U.S. maintained a heavy military presence along the border. President Wilson also sent troops into Mexico on two occasions, invading and occupying the port city of Veracruz in 1914 and conducting the "Punitive Expedition" under General John J. Pershing in 1916 after Pancho Villa raided the town of Columbus, N.M., and killed more than a dozen Americans.

Operation Wetback

Beginning in 1954, Attorney General Herbert Brownwell launched the offensively titled Operation Wetback intended to round up and remove more than 1 million Mexican immigrants that were believed to be in the country illegally. Brownwell sought to coordinate the Border Patrol with the Army, but the request was rejected.

University of California Los Angeles history professor Kelly Lytle Hernandez said federal troops stayed out of the operation due to the Posse Comitatus Act, which prohibited the use of military personnel to enforce domestic policies. But the Border Patrol was aided with military equipment.

The war on drugs

Army Gen. Colin Powell established Joint Task Force Six, expanding the military's role in the war on drugs under former president George H.W. Bush on Nov. 13, 1989. The task force, comprising active-duty and reserve troops, operated out of Fort Bliss, Texas, and aids in law enforcement in anti-drug efforts along the border.

According to the Department of Defense, the task force, now known as Joint Task Force North, has conducted more than 6,400 missions and has assisted in the seizure of $15.2 billion in illegal drugs in the last 16 years.

Operation Jump Start

Former president George W. Bush deployed 6,000 National Guard members to California, Arizona, New Mexico and Texas in 2006 to assist Border Patrol operations. The two-year deployment cost $1.2 billion.

According to the Pentagon, under Operation Jump Start, the National Guard assisted in more than 176,000 apprehensions as well as the seizure of more than 316,000 pounds of marijuana and 5,224 pounds of cocaine.

Operation Phalanx

Then-president Barack Obama ordered the deployment of 1,200 National Guard troops to support the Border Patrol in 2010. According to the U.S. Customs and Border Protection agency, the National Guard assisted in nearly 18,000 apprehensions and the seizure of more than 56,000 pounds of marijuana during the first year of the operation.

The program cost $110 million during its first year.

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