Governments have always sought to manage public perception in wartime, but the Israel Defense Forces’ steady stream of updates on Twitter, YouTube and Facebook since it began airstrikes on the Gaza Strip on Wednesday seems different. Unlike the usual media tactics — leaflets, state-sponsored radio, spokesmen — social media campaigns seek to incorporate themselves into the media we’re already consuming, popping into our news feeds, implicitly seeking our participation. Or, in the case of the IDF campaign, sometimes explicitly.

The @IDFSpokesperson Twitter account, encouraging followers to show support for the strikes, tweeted Wednesday: “More than 12,000 rockets hit Israel in the past 12 years. RT if you think #Israel has the right to defend itself.” More than 5,500 people have retweeted it. On Facebook, a flier-style image with a similar message has been shared 18,000 times. 

But it’s hard to measure whether the IDF’s campaign is changing minds or just reinforcing existing ideological divides. When Egyptian activists launched a grass-roots social media campaign during the early 2011 Arab Spring protests that culminated in revolution, they used Facebook to organize and Twitter to attract the world’s attention and, ultimately, its sympathy. The IDF is plenty organized without social media’s help; its campaign has certainly attracted attention, but not necessarily the sort that will further Israel’s interests.

An early tweet announced the targeted killing of a senior Hamas military commander, Ahmed al-Jabari, with a headshot, tinged blood-red, bearing bullet points of his terrorist acts and the word “eliminated” stamped in capital letters. As fighting escalated, the IDF tweeted, “We recommend that no Hamas operatives, whether low level or senior leaders, show their faces above ground in the days ahead.”

Most messages have chronicled Hamas’s very real crimes, Israelis’ suffering under their rockets and the IDF’s strikes. The accounts have mentioned Gazan civilians, though typically alongside reminders that the IDF has dropped fliers warning them to “take responsibility for yourselves and avoid being present in the vicinity of Hamas operatives and facilities.”

The campaign has elicited a strong reaction. A significant number of Israelis and Americans (whom one IDF tweet addressed directly) have retweeted, liked, shared and otherwise shown their support for the Israeli military operation, dubbed Pillar of Defense.

Skeptics, particularly in the Arab countries surrounding Israel, have seemed to consider the tweets and posts overly triumphant or insensitive. The IDF’s campaign became a heated topic in the larger social media discussion of the military operation. Its official ­#PillarOfDefense hashtag has attracted a small fraction of the discussion linked to the Gaza-sympathetic hashtag #GazaUnderAttack. 

Hussein Ibish, a D.C.-based senior fellow at the American Task Force on Palestine, tweeted, “This is extremely damning: IDF cheerily live-tweets infanticide.” (By the end of the week, the death toll in Gaza had reached 39, including a young child.)

The criticism has not been limited to Middle Easterners. Irish Twitter account @Ard_Macha said of the social media push, “Probably more disturbing than the attack on Gaza is the apparent glee with which the IDF carries out its job.”

A polished, edgy campaign can’t overturn actual public opinion, which still rules social media. But it can remind people of what they already think, giving them an opportunity to sound off for or against, and to dig up the debates they’ve been having for years. Like a spree of attack ads in a political campaign, the effect has been polarizing — deepening divides that were already problematic for Israel.

Public opposition to Israel’s Gaza policies was already high in neighboring Egypt, for example, where a newly democratic, Muslim Brotherhood-allied government will have to decide how to respond. An attention-grabbing, feather-ruffling campaign risks further inflaming a public opinion that suddenly matters for Egypt’s decision-makers in a way that it didn’t under Hosni Mubarak’s reliably pro-Israel dictatorship.

President Mohamed Morsi isn’t going to unilaterally withdraw from the Camp David Accords over a few tweets, but the less pressure he feels from anti- Israeli activists and Muslim Brotherhood factions, the better Israel is likely to be served.

That’s the problem with social media. Once you start feeding it posts and images, users can send them swirling just about anywhere. You might think you’re just talking to your friends, but you don’t really control the conversation, which can take on a breadth and significance you hadn’t intended.