WASHINGTON — Abraham Lincoln’s words were chiseled in granite. John F. Kennedy’s words are embedded in the national consciousness.

A year into President Trump’s term, his most memorable lines come not from grand speeches or prime-time presidential addresses. They come from his tweets.

Sad?

Perhaps, but Trump’s direct Twitter channel to America has proved its potency in his first year in office.

Twitter is where Trump deems anything negative as “fake news.’’ It’s where people and policies are a “disaster,’’ where “the Russia-Trump collusion story is a total hoax,’’ despite a steady drumbeat of fresh disclosures.

The commander in chief loves ALL CAPS and exclamation points!!! He is unimpeded by grammar or spelling conventions.

Then there’s the name-calling from the White House. The leader of North Korea is “Rocket Man,’’ the senior Democratic senator from Massachusetts is “Pocahontas.’’ Senator Bob Corker from Tennessee, a fellow Republican no less, is “incompetent,’’ “doesn’t have a clue,’’ and “couldn’t get elected dog catcher.’’

Trump stormed Washington and upended the White House and other storied institutions during his inaugural year. And to the delight of his fans and horror of his detractors, he used his Twitter feed as a tool of disruption, continuing his campaign practice of delivering social-media trauma on his enemies.

The impulsive president can bring Washington to a halt and dominate cable news for days with a single tweet. His tweets have been cited in lawsuits, and they have been used to announce new federal policies. Sometimes federal officials charged with carrying out his orders have found out their new mission via Twitter, at the same time as the president’s nearly 45 million followers.

He is making history with his thumbs and fingers. Just as Franklin Delano Roosevelt mastered radio in his time and JFK had his telegenic image beamed into living room television sets, Trump has pioneered a way to communicate directly to citizens. And for a president who has eschewed holding presidential news conferences, his Twitter account is one of the few ways for the public to hear from him directly.

“All presidents try to find new ways to communicate, and Trump has kind of flummoxed his critics who told him to drop Twitter,’’ said presidential historian Doug Brinkley. “He does it anyway, and it seems to keep his base placated.’’

But Trump’s unique, at times bullying style on Twitter also alienates many Americans, Brinkley said, and it has limited his ability to broaden his support, amplifying his polarizing effect.

“He views presidential politics as like an Electoral College board game, and he’s thinking of ‘Monopoly’ and how you play and how do you collect the real estate, how do you collect the pieces,’’ Brinkley said. “He is a lot more of a political animal than people realize. But he just takes civility and shame and standards and has flushed them down the national toilet.’’

The White House did not respond to requests for comment.

Since Trump’s swearing-in, there have been 2,417 posts from his account, according to a Globe review. If he spent only one minute on each post, that would be nearly 40 hours. That’s a solid workweek of nonstop tweeting.

The phrase “fake news’’ appeared 159 times, more than almost any other, according to a Globe review of his first-year tweets. He used the word Democrats (or Dems) more times (165) than he did Republican or GOP (143). He mentioned jobs 92 times. But he was less likely to mention terms related to immigration, citing the border 55 times and the wall 29 times.

He tagged the account of “Fox & Friends’’ 96 times, far more than any other. Almost all of the other accounts he tagged were related to the White House, although he cited The New York Times 30 times, almost always by derisively calling it the “failing @nytimes.’’

Among countries, Trump mentioned Russia the most — 96 times — often because he was tweeting about the investigation into whether his campaign colluded with Russia.

“It is now commonly agreed after many months of COSTLY looking that there was NO collusion between Russia and Trump,’’ he wrote in October. “Was collusion with HC!’’

Since becoming president, he’s had at least 48 tweets about Hillary Clinton — referring to “Crooked Hillary’’ 24 times — and he’s had 54 tweets about Barack Obama.

It is foreign policy where his tweets can pose the biggest risks, say specialists. In September, he began referring to North Korean leader Kim Jong Un as “rocket man,’’ disparaging an international leader (with access to nuclear weapons) in the same way as his domestic political opponents.

“I told Rex Tillerson our wonderful Secretary of State that he is wasting his time trying to negotiate with Little Rocket Man,’’ he wrote one October morning.

“Being nice to Rocket Man hasn’t worked in 25 years why would it work now? Clinton failed Bush failed and Obama failed. I won’t fail,’’ he added a few hours later.

In his tweets, Trump mentioned North Korea 59 times, and China 46 times.

Michael O’Hanlon, a foreign policy expert at the Brookings Institution, said that some of Trump’s tweets are “entirely unproductive,’’ particularly some that have disparaged British leaders. But others could have some promise, including an approach to North Korea that seems to promote the idea that Trump is unpredictable

“I can’t say Trump’s tweets toward North Korea have been beneficial,’’ O’Hanlon said. “But Trump being himself at least has the potential to be integrated into a broader strategy that may hold some promise.’’

“It’s a very risky strategy. At any given moment, it could take us off the rails,’’ he added. “But in fairness to Trump, all the other strategies we have tried have been risky as well.’’

O’Hanlon has also noticed a difference in how different parts of the world treat the tweets.

In Asia, many leaders look for bottom-line policy pronouncements, largely overlooking the brash online persona, while in Europe they follow the presidential Twitter feed closely.

“Europeans get us well enough to understand that President Trump is a bit of a narcissist and an impulsive actor. And they’re put off by that. They’re more offended than other parts of the world,’’ he said.

Trump’s Twitter feed can create headaches for the White House, particularly when aides have to respond to something they themselves are just learning about. White House chief of staff John Kelly, who took over the role in July, has tried to create more order, in part by paying less attention to the president’s online commentary.

“Believe it or not, I do not follow the tweets,’’ Kelly told reporters last month, adding, “The tweets don’t run my life — good staff work runs it.’’

Many of Trump’s most inflammatory comments come when he is alone in the White House residence, early in the morning, before the West Wing starts humming: A third of his activity on Twitter took place between 5 a.m. and 8 a.m., according to the Globe analysis.

“My use of social media is not Presidential - it’s MODERN DAY PRESIDENTIAL,’’ he wrote in July. “Make America Great Again!’’

Long before entering office, Trump seemed fascinated by Twitter as he learned to master a medium that almost by design can feel pithy and conversational.

On a Friday afternoon in August 2012, he noted, “It’s Friday. How many bald eagles did wind turbines kill today? They are an environmental & aesthetic disaster.’’ He had opinions on whether stars from the movie “Twilight’’ should break up, on the quality of the Academy Awards, and on Rosie O’Donnell.

His Twitter feed was used to settle scores and offer late-night cable news commentary. As president, little has changed.

Trump last month retweeted anti-Muslim videos sent by the far-right group Britain First, and earlier this year he ridiculed London Mayor Sadiq Khan in the aftermath of an attack. Both instances triggered widespread condemnation from top leaders in Great Britain, the longtime US ally.

“It is Donald Trump’s stream of consciousness quite often,’’ said Doug Heye, a longtime Republican consultant. “That has good and bad aspects. It means he can inject anything into the political discussion anytime he wants to. The downside is that can be anything.’’

“What has been frustrating to a lot of people is when we’ve had a good jobs report and we spend it not talking about that because Trump . . . tweets about the outrage du jour, or he creates the outrage du jour,’’ he added. “Too often we step on good economic news.’’

Trump has frequently contradicted himself, to the point where a spoof Twitter account was established in April to mark all of his flip-flops. He urged Obama to get congressional approval for actions in Syria, and then as president took actions in Syria without congressional approval. He complained about Obama signing executive orders, and then he signed executive orders. He derided the amount of time Obama went golfing, and then he went golfing even more.

Trump in 2013 mocked Senator Marco Rubio on Twitter for lurching for a plastic water bottle in the middle of a response to the State of the Union address. A glass would have been much more classy, he noted.

But Trump himself, as president, recently lurched for something to wet his palate and, yes, it was a plastic water bottle.

“The electoral college is a disaster for a democracy,’’ Trump wrote after the 2012 election.

“The electoral college is actually genius in that it brings all states, including the smaller ones, into play. Campaigning is much different!’’ he wrote four years later, when he lost the popular vote but became president because of the Electoral College process.

One sign of the limits of his account: When Twitter released its most-shared tweets of 2017, Trump did not make the list. But his predecessor, Barack Obama, had three tweets on the list.

Still, for all of America’s obsession over Oval Office tweets, what was the top tweet of the year?

A 16-year-old from Reno who launched a campaign to win a year’s supply of free chicken nuggets from Wendy’s.

Victoria McGrane of the Globe staff contributed to this report. Matt Viser can be reached at matt.viser@globe.com.