(CNN) Protesters flooded Washington and gathered in many other cities Saturday to take a stand on President-elect Donald Trump's inauguration. The protesters hoped to send a strong message to the world that they oppose this commander-in-chief. They want to make it clear that Trump does not have a mandate to take America in a new direction and that he doesn't represent the values of the nation.

Anna Galland, executive director of MoveOn.org, explained to The New Yorker: "I cut my teeth as an organizer in the movement opposing the Iraq war. I feel that was a smaller trial run for what we're going to be seeing right now."

This is not the first time that a president's inaugural celebration has been been marred by protest.

Richard Nixon experienced opposition at both of his events. In 1968, the Mobilization Committee to End the War in Washington came to town, with some of the activists throwing bottles and food at the presidential motorcade and holding signs critical of the new president. About 200 anti-war protesters were able to obtain bleacher seats on Pennsylvania Avenue, from which they waved flags of the National Liberation Front.

In January 1973, following Nixon's landslide reelection victory against George McGovern, the protests were back. Almost 100,000 protesters massed at the Washington Monument, with some marching toward the Lincoln Memorial. The protesters carried signs with the names of Vietnamese battlefields as well as domestic needs -- like housing for the poor -- that were unaddressed because of spending on the war.

The Bush inauguration protests

Another famous moment of large-scale inaugural protest took place when George W. Bush prepared to take his oath of office in January 2001.

Many Americans, particularly Democrats, did not believe that he had won a legitimate victory against Vice President Al Gore. Bush lost the popular vote and won the Electoral College only when the Supreme Court stopped a recount in the contested state of Florida.

Tens of thousands of protesters were on hand at the inauguration to state their views. Some stood before the Supreme Court holding signs that read: "Obey" and "Kneel Before Bush." They expressed their "outrage about the trampling of the electoral process and the disenfranchisement of voters," according to the organizer of the Voter March. They waved flags that read "Hail to the Thief" as Bush's limo drove by the crowd.

At a rally near the Capitol, the Rev. Al Sharpton told the crowd: "George Bush was not elected by the people. He was selected by the judges of the Supreme Court, and those judges ought to know that they cannot rob from us."

In the end, however, the protests had only limited impact, a lesson that today's activists should remember.

Despite the controversial election, President Bush governed like he had a mandate. Before 9/11, he pushed through bold initiatives like a supply-side tax cut and the No Child Left Behind Act. After 9/11, he undertook a dramatic expansion of the government's counter-terrorism program and launched two ground wars.

In the case of Nixon, the Watergate scandal was what brought him down more than anything the protesters accomplished. Without the scandal, which was of his own making, Nixon was on his way to a transformative two-term presidency.

Taking it beyond marches

For President Trump's opponents to succeed, the inauguration marches can only be a first step.

Two new publications point to a path forward for his Democratic opponents. In " Indivisible: A Practical Guide for Resisting the Trump Agenda ," former congressional staffers turn to the tactics that Tea Party Republicans used against President Obama as a model for opposing Trump.

The online booklet outlines a defensive strategy to stop Trump's agenda. The key, according to the authors, is understanding the basic fact about Congress -- legislators are electoral creatures whose main concern is reelection. With that in mind, the key to successfully stopping a president is to create enough grass-roots pressure on Congress at the local level so that members fear that supporting the White House will threaten their own electoral future.

The publication suggests a number of tactics to achieve this goal, all of which need to take place at the points of contact that citizens have with legislators -- town halls, ribbon-cutting ceremonies, district offices and through phone banks.

The authors walk readers through a step-by-step process of building and managing strong local groups to carry out this political warfare. The document offers reminders like "Record Everything! Assign someone in the group to use their smart phone or video camera to record other advocates asking questions and the response from the member of Congress. While written transcripts are nice, unfavorable exchanges caught on video can be devastating."

"Indivisible" makes it clear that liberals need to constantly make their opposition to Trump's proposals known in front of legislators and in front of television cameras.

"Be prepared to interrupt and insist on your right to be heard," they suggest. Legislators must have the perception within their districts and states that there is a real risk of voting in favor of anything that President Trump puts before them.

Rebuilding the Democratic Party

The veteran political scientist Theda Skocpol, in an article titled, "A Guide to Rebuilding the Democratic Party, from the Ground Up," is more interested in how Democrats can rebuild their party after losing the White House, Congress, 18 governorships and 33 state legislative bodies.

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Turning away from replaying the debates about the elections or talking about "messaging," Skocpol urges Democrats to devote their resources toward concrete measures that can build the standing of their party. This means paying close attention to the organizational strength of state party organizations and making sure there are enough paid staffers to work with volunteers in elections.

She calls for a more muscular Democratic National Committee that will work harder on finding groups to supplant the heavy lifting that organized labor used to do for the party in their heyday during the 1950s and 1960s.

She urges Democrats to put more money into political intelligence, gathering better data about how people will behave politically -- rather than learning about what they believe in -- and developing better strategies about how to sell their programs to the public rather than assuming that good policies will automatically win support.

Finally, Skocpol implores Democrats to replicate what Republicans did in 2010—pour enormous amount of money and manpower into the 2018 gubernatorial and state legislative races so that the Democrats have more muscle in the next round of redistricting.

Both of these publications are essential guidance if Democrats want to do something more than vent their anger at the inauguration. And as the nation celebrates the life of Martin Luther King, Jr., it is a good time to remember what the long haul of sustained citizen activism can bring.

If this weekend's protests are to be successful, they must be a launching pad for the party to start a long-term process of fighting against what is looking like a radically conservative administration and of rebuilding their party.

Otherwise, these protests will look much more like the "Not My President" marches that took place right after the elections -- flash-in-the-pan moments in cities like New York and San Francisco that garnered a few hours of media attention but didn't amount to very much in the long run.