Graham, of course, is a top GOP voice on matters of foreign policy, so to see him jousting with the president isn't terribly surprising.
But it's hard not to look at these things in a political context, and Graham has lots to gain personally by becoming a high-profile critic of Obama.
After two election cycles in which tea party and conservative groups have taken down a number of incumbent senators and establishment candidates who were viewed as insufficiently conservative, Graham now finds himself as the RINO-du-jour for many of these groups in the 2014 primary season.
While Graham is a pretty down-the-line conservative on matters of foreign policy, socially and economically conservative groups have never been happy with him -- particularly coming from a reliably red state -- and Graham has irritated conservatives by voting for Obama's Supreme Court nominees on the Senate Judiciary Committee and working with Democrats on climate change.
“Looking to the horizon of 2014, you know, the sun may rise over South Carolina,” Club for Growth President Chris Chocola told reporters in September. "There is interest beyond our group in that race."
That becomes a tougher task when they guy you're trying to unseat is on TV every day saying something hugely critical of the Democratic president.
We've seen this story before.
Sen. Orrin Hatch (R-Utah), having seen what the tea party did to his colleague Sen. Robert Bennett (R-Utah) two years prior, staked out some very conservative territory in his primary this year and won reelection easily, for example.
But for Graham, it's not quite so simple. While he can be Obama's top foe when it comes to Libya, he's in line to become a top ally when it comes to immigration reform. Graham has been pushing for comprehensive immigration reform for a while now and continues to promise to lead his party toward a deal now that there is a desire in the GOP to get something done.
Despite that desire to get something done, though, it's not clear that the GOP base will happily go along with it. And if there is pushback, with Graham leading the charge for middle ground, that could severely hurt his primary prospects in 2014 -- about as much as the Libya criticism can help them.
The relationship between Obama and Graham is sure to be one of the more fascinating interactions of the 2014 election cycle. Keep an eye on it.