How past US presidents engaged with activists and mass protests

A narrow gap between protesters and riot police during a demonstration against the Vietnam War in Washington, DC, on May 21, 1972. (Archive Photos/Getty Images)

(CNN) -- As Americans engage in demonstrations around the country calling for an end to police brutality, President Donald Trump has opted to return to his call for “law and order.”

And though he's said he's sympathetic to peaceful protesters, ​he's threatened military force and urged states to empower police to arrest more demonstrators. He's singled out agitators as members of the "radical left." And he's also tweeted ​that the self-described anti-fascists, Antifa, ​will be classified as a terrorist organization. (Though the US government has no apparent legal authority to do so.)

On Monday evening, he declared in a speech that he was the "law and order" President as security forces could be heard battling with peaceful protesters on the streets near the White House. Moments after the protesters had been moved, Trump walked down the same streets to pose with a Bible at a church damaged by earlier demonstrations.

Past US presidents have had varying approaches to mass protests and activism. Some were reluctant to bring up their causes, but were eventually pushed by politics. Others ignored calls from the masses or charged them with unruly behavior. Others brought them into the White House for discussions.

Here's a look back at how recent American presidents engaged with protest movements:

Kennedy and Johnson during the Civil Rights Movement

President John F. Kennedy delivered an Oval Office address on June 11, 1963, proposing anti-discrimination and anti-segregation legislation.

That address, according to the Miller Center at the University of Virginia, happened "only after the effective and public grassroots movement brought international attention to the violence and undemocratic reality of segregation and forced him to take a stand."

In 1963, Martin Luther King Jr.'s "I Have a Dream" speech and march on Washington was credited with bolstering support for Kennedy's proposed civil rights legislation. The day of the march, Kennedy met with civil rights leaders in the Oval Office.

President Lyndon B. Johnson made civil rights a main tenet of his Great Society agenda after Kennedy's death, which propelled the Civil Rights Act of 1964 and the Voting Rights Act of 1965 through Congress.

In the wake of riots across the country over King's assassination, Johnson signed the Civil Rights Act of 1968 into law. The legislation also made certain actions relating to inciting a riot a felony under federal law.

Johnson and Nixon during the Vietnam War

Johnson, facing pressure from anti-war advocates and the potential emergence of an anti-war Democratic presidential challenger, surprised Americans when he announced he would not be running for reelection in March 1968.

Johnson said in an Oval Office address that during the Vietnam War, he felt he should not be devoting time to "any personal partisan causes or ... any duties other than the awesome duties of this office."

The announcement came after the launch of the Tet Offensive, which was proving successful for North Vietnamese communist troops.

It sparked a new wave of anti-war protests, including when thousands of anti-war protesters clashed with police and the National Guard outside the Democratic convention in 1968. Richard Nixon, accepting the Republican presidential nomination, pledged to lead America with "law and order" following the anti-war protests as well as the assassinations of Martin Luther King Jr. and Robert Kennedy.

The war in Vietnam waged on and in 1969, the US draft lottery sowed further division among Americans about the war.

In his second address to the nation on the Vietnam War, Nixon called for "the great silent majority" of Americans to voice their support for his war policies.

Anti-war demonstrations turned deadly at Kent State University in 1970, when four students were killed by the Ohio National Guard. After the incident at Kent State, Nixon went to the Lincoln Memorial near dawn to meet and talk to anti-war demonstrators.

Nixon wouldn't halt direct US involvement in the Vietnam War until 1973.

Reagan and George H.W. Bush during the AIDS crisis

Ronald Reagan garnered early support for his presidential run from the Moral Majority, a conservative Christian group whose leader, Jerry Falwell, referred to AIDS as "God's punishment for homosexuals."

And in 1985, the White House would hire Pat Buchanan as a communications director. Two years earlier, he'd written in an op-ed that homosexuals "declared war upon nature, and now nature is exacting an awful retribution" in the form of the AIDS epidemic.

Reagan delivered his first major address on AIDS at the American Foundation for AIDS Research in 1987, discussing AIDS in public for the first time since the start of his presidency in 1981. ​More than 24,000 people had already died from complications of HIV.

According to the San Francisco AIDS Foundation, it wasn't necessarily activists and media attention that swayed Reagan. The address came two years after the death of the Reagans' close friend, actor Rock Hudson, from AIDS-related complications, and Reagan reportedly attended the AmFAR event at the urging of actress Elizabeth Taylor.

A march on Washington for Lesbian and Gay Rights was held later that year, headlined by acts of civil disobedience at the Supreme Court and the first display of the AIDS Memorial Quilt.

Then George H.W. Bush came into office in 1989 and during his presidency signed the Americans with Disabilities Act, which included anti-discrimination protections for people with HIV/AIDS, and the Ryan White Comprehensive AIDS Resources Emergency Act.

But his administration was also reluctant to change a policy blocking people with HIV from entering the country. And during his presidency, AIDS activists held several demonstrations calling on the federal government to do more for Americans with HIV/AIDS, including showing up to his Maine compound and scattering the ashes of people who died of AIDS on the White House lawn.

According to the Washington Blade, Bush said in 1991 that he thought activist group ACT UP's tactics were "totally counterproductive" and "an excess of free speech."

Clinton on abortion protesters

On the 20th anniversary of the Roe v. Wade Supreme Court case decision in 1993, President Bill Clinton lifted several Reagan-H.W. Bush-era abortion restrictions.

And in 1994, Clinton signed a bill into law expanding federal penalties for the use of violence against those who seek and provide abortions.

The legislation came in the wake of increased anti-abortion protests at clinics and the murder of Dr. David Gunn in 1993. Gunn was an OBGYN who performed abortion services at different clinics. He was shot as he was walking into one of those clinics by a man who was part of an anti-abortion protest.

Speaking about the actions at a signing ceremony, Clinton said: "We simply cannot -- we must not -- continue to allow the attacks, the incidents of arson, the campaigns of intimidation upon law-abiding citizens that has given rise to this law."

George W. Bush and the Iraq War

President George W. Bush said in 2003 that he wouldn't be swayed by the sizes of mass protests against the US invasion of Iraq to make his decision to go to war or not.

"Size of protest, it's like deciding, 'Well, I'm going to decide policy based up on a focus group,'" Bush said, according to PBS.

"The role of a leader is to decide policy based upon the security -- in this case -- security of the people."

In the same exchange, he acknowledged that "people are allowed to express their opinion, and I welcome people's right to say what they believe."

Obama and the Tea Party, Black Lives Matter

President Barack Obama's policy proposals were met by protesting conservatives who formed into the conservative Tea Party early in his presidency.

In 2011, Obama told The Associated Press that he acknowledged that the Tea Party movement "forced some questions to surface about who we are as a people and what can we afford."

In 2014, Obama addressed property destruction during the protests in Ferguson, Missouri. The demonstrations emerged against police brutality following the police killing of Michael Brown, and Obama said he had "no sympathy at all for destroying your own communities" and urged protesters to avoid a second night of violence.

The following year, Obama said that although he didn't think the abuses of power in Ferguson were "typical ... it's not an isolated incident."

He also met with Black Lives Matter activists as well as law enforcement officials and community leaders at the White House in 2016.