On Jan. 20, President Barack Obama will be sworn into office, marking another four years of high hopes and measured expectations. In the images that follow, we revisit the milestones that shaped his first term in office, each one raising the temperature of the nation to varying degrees. Beginning with Nov. 4 2008, we view these moments through our culture’s wildly fluctuating barometer of public opinion: Twitter. It happens that the year Obama made history was also the year Twitter took off.. It grew in visitors by 752 percent in 2008, while Obama harnessed the platform to expand and mobilize his base of supporters. Ahead, see how the president has watched over the country in the years that followed Election Day ’08, and how the most spirited tweeters have in turn kept watch on him.

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  • Nov. 4, 2008: Election Day

    “We just made history. All of this happened because you gave your time, talent and passion. All of this happened because of you. Thanks.” — @BarackObama

  • Nov. 7, 2008: Obama Apologizes To Nancy Reagan For Seance Remark

    ” Obama is now apologizing to Nancy Reagan. Good grief.” — @rgutel

  • Jan 21, 2009: Obama Signs Order For Pay Freeze For Staffers, Lobbying Rules, On First Day In Office

    “I like watching Obama undo stupid crap that Bush did. POW, just like that. Sometimes is IS that simple.” — @ jessamyn

  • April 14, 2009: Bo Obama Moves In

    “I am not an ideologue. I’m an ideal dog.” — @BoObama (unofficial)

  • June 4, 2009: Obama Visits Cairo, Makes Key Middle East Speech

    “I guess Obama’s Cairo Speech really worked out. The Muslim Brotherhood stormed our embassy on 9.11. Imagine if Obama speaks in Beijing?” — @realdonaldtrump, 09.12.12

  • March 23, 2010: Obama Signs Health Care Reform Bill

    “You know what you should do today? Hug a rich person. They are paying for your way of life. #tcot #hcr.” — @ingrahamangle (Laura Ingraham)

  • December 22, 2010: Obama Signs The Repeal Of ‘Don’t Ask, Don’t Tell’

    “Today we stand taller declaring: ‘I am somebody.’” — @ltdanchoi

  • April 27, 2011: Obama Releases Long-Form Version Of His Birth Certificate

    “high gas prices, unemployment, OBAMA’S BIRTH CERTIFICATE, the educational system in America...which one is not that important..?!” — @kirkfranklin

  • April 30, 2011: The White House Correspondents Dinner

    “Obama going to town on Trump. And it is awkward with a capital ‘A’ around his table. I mean, big time.” — @thefix “Somebody tell that idiot Obama he’s not funny #nerdprom #whcd #tcot.” —@trumpforprez

  • May 2, 2011: Osama Bin Laden Is Killed

    “Helicopter hovering about Abbottabad at 1AM (is a rare event.” Eight hours later... “Uh oh, now I’m the guy who liveblogged the Osama raid without knowing it.” — @ReallyVirtual

  • June 22, 2011: Obama Announces Troop Drawdown In Afghanistan

    “Mr. President, our ‘troops in Afghanistan are coming home’? Why am I set to go there this summer, sir? I’m confused. Your wording is tricky.” — @artilleryanon

  • Jan 25, 2012: Obama’s Tense Exchange With A Finger-Pointing Jan Brewer

    “I suppose Obama wanted Jan Brewer to kiss his ring. He’s showing her that you don’t point a finger at the king and get away with it.” — @scuzzydirtbag

  • May 9, 2012: Speaking To Robin Roberts, Obama Officially Endorses Gay Marriage

    “Same sex couples should be able to get married.” — @BarackObama

  • June 28, 2012: Supreme Court Upholds Health Care Mandate

    “Mitt Romney says #obamacare is a ‘job killer.’ You know what’s a ‘people killer’? NOT HAVING HEALTHCARE.” — @harikondabolu

  • Sept. 9, 2012: Obama Picked Up By Restaurant Owner Scott Van Duzer During Campaign

    “Thank you, Scott Van Duzar [sp], for lifting the entire country when you gave Pres. Obama a hug.” — @kkalmes2

  • Sept. 12, 2012: Obama Makes A Statement On Benghazi Attack

    “America: ‘We want the truth about #Benghazi!’ Obama: ‘Maybe later. Maybe. Vote for me!’ — @galtsgirl

  • Oct. 3, 2012: First Obama-Romney Debate

    “Obama is waiting for the right moment to pull out Bin Laden’s skull from behind the podium. Wait for it. Wait for it…” — @chrisrock

  • Nov. 6, 2012: Obama Is Reelected

    “Four more years.” — @BarackObama, in a tweet with this image, which became the single most-retweeted message in Twitter history

  • Dec. 14, 2012: Obama Briefed On Sandy Hook Shooting

    “Today President Obama rightly sent his condolences to families. But the country needs him to send a bill to Congress.” — @mikebloomberg

This story appears in Issue 32 of our weekly iPad magazine, Huffington, in the iTunes App store, available Friday, Jan. 18.

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