For non-Americans: the State of the Union is an annual address in which the president outlines how the country’s doing and the agenda for the future.
Which parts of Obama’s address particularly resonated with the public? One can judge the congressional response to each line by listening to applause in the chamber, but it's harder to know what the country as a whole thought. One way to find out is to look up every single sentence in the speech on Twitter and study each response. Yes, this took a while, and yes, I should probably find other hobbies, but the results were worth it.
Each point in the graph below represents a single sentence, ordered from left to right by order in the speech; the height of the point represents how many people retweeted it.
What is that point in the upper-right corner, the quote that is shared 10 times as widely as any other line in the speech? Surely it must be some rhetorical masterstroke, a particularly inspired policy proposal? No: it's the ad-libbed moment in the speech where Obama puts down the Republicans.
We criticize our politicians for lack of civility, but how do we expect them to behave when we pay more attention to their snappy retorts than their policy proposals?
Zooming in on the graph (click here and mouse over points to see which quotes they represent) we see that many of the most widely shared lines reprise the messages of hope and unity that so resonated when Obama originally took office: "I still believe we are one people", "I still believe that together, we can do great things", and "Let's begin this new chapter -- together -- and let's start the work right now". (More substantive lines, like those about gay marriage, community college, middle-class economics, and climate change, were also shared widely).
The only problem with these pleas for unity? For the most part, only the Democrats found them compelling. Self-identified liberal tweeters outnumbered self-identified conservative tweeters more than two to one for every single one of the top 25 most retweeted lines in the speech. Among those sharing "My fellow Americans, we too are a strong, tight-knit family", I could identify 96 liberal tweeters and only 5 conservative tweeters : perhaps not such a tight-knit family after all.
So what lines were shared among Republicans? Here are the lines whose retweeters skewed most conservative (among lines shared by at least five tweeters with identified political affiliation).
Republicans / Total
Already, we've made strides towards ensuring that every veteran has access to the highest quality care.
Helping hardworking families make ends meet.
In Iraq and Syria, American leadership -- including our military power -- is stopping ISIL's advance.
There are no guarantees that negotiations will succeed, and I keep all options on the table to prevent a nuclear Iran.
We need to do more than just do no harm.
That's what middle-class economics is -- the idea that this country does best when everyone gets their fair shot, everyone does their fair share, and everyone plays by the same set of rules.
Of course, just because conservatives were sharing Obama's words doesn't mean they agreed with them. For example, "Already, we've made strides towards ensuring that every veteran has access to the highest quality care" was shared by conservatives with the addendum "This one difficult to take". "We need to do more than just do no harm" was shared by conservatives who replied, "PLEASE DON'T".
Sometimes differences between the political parties emerged even in consecutive lines of the speech. For example, when Obama said "And today, America is number one in oil and gas. America is number one in wind power," 68% of people sharing the line about oil were conservative; 82% of people sharing the line about wind power were liberal.
Of course, political party isn't the only characteristic that affects how we react to a speech. Men and women  reacted in different ways as well.
Lines Whose Resharers Were Most Likely to Be Female
Lines Whose Resharers Were Most Likely to Be Male
That's why this Congress still needs to pass a law that makes sure a woman is paid the same as a man for doing the same work.
Instead of getting dragged into another ground war in the Middle East, we are leading a broad coalition, including Arab nations, to degrade and ultimately destroy this terrorist group.
I want our actions to tell every child, in every neighborhood: your life matters, and we are as committed to improving your life chances as we are for our own kids.
We can't slow down businesses or put our economy at risk with government shutdowns or fiscal showdowns.
It's time we stop treating childcare as a side issue, or a women's issue, and treat it like the national economic priority that it is for all of us.
We believed we could reverse the tide of outsourcing, and draw new jobs to our shores.
[Child care]'s not a nice-to-have -- it's a must-have.
Members of both parties have told me so.
Today, we're the only advanced country on Earth that doesn't guarantee paid sick leave or paid maternity leave to our workers.
We still need to make sure employees get the overtime they've earned.
That's why we defend free speech, and advocate for political prisoners, and condemn the persecution of women, or religious minorities, or people who are lesbian, gay, bisexual, or transgender.
Today, we have new tools to stop taxpayer-funded bailouts, and a new consumer watchdog to protect us from predatory lending and abusive credit card practices.
We still may not agree on a woman's right to choose, but surely we can agree it's a good thing that teen pregnancies and abortions are nearing all-time lows, and that every woman should have access to the health care she needs.
If we don't act, we'll leave our nation and our economy vulnerable.
Beyond gender and political party, people’s backgrounds guide their reactions in many subtler ways. Tweeters who reshare the speech’s quote from Pope Francis are more likely to describe themselves as Catholic; those who reshare figures on Iraq and Afghanistan are more likely to be veterans, and those who reshare figures on graduation rates and test scores are more likely to be educators.
After I completed this analysis, I could see why Obama’s speechwriter needs a stiff drink. He had to please a thousand different constituencies in a single speech, half the country wasn’t going to be happy no matter what he said, and the line that people liked best wasn’t even in his draft. I’ll stick to writing code.
 Most tweeters do not identify their political affiliation in their profile, so this approach works only for a small subset of tweeters.
 I used the name of the tweeter to identify their gender. This does not work for all tweeters, and it does not account for people whose gender does not fit a binary description or does not match that implied by their name, but I still think it’s worth doing on balance because it gives a useful (if noisy) signal.