And other twitter hashtag foreign policy efforts.
I believe this also constitutes Kony and Darfur (or Sudan in general) and then something like Iran's green revolution or unrest in places like Turkey.
First. What is this intended to do. I suspect, as with Syria and Ukraine, there appears to be belief, usually among liberals in this case, that our military power is sufficient to bully or intervene in many, many cases with great and immediate success. There are examples where this may be the case, but we still have troops hunting Joseph Kony in Uganda (and/or surrounding territory), still have a Libya in turmoil, the Balkan states where we intervened are a mess, and so on. This should counsel against the idea that American power or the mere mention of American power is sufficient to make other people behave the way we would prefer in other countries, and that our interventions will achieve something we value as an end goal.
This is quite apart from the question over whether what is happening somewhere on the globe is a tremendous injustice. Kidnapping and endangering school children is a grave damage and injustice. Killing thousands of civilians in a civil war or general civil unrest is a more serious injustice. We can weight these to decide whether our interventions may be more justified, or decide any serious injustice abroad that asks for our intervention (or an international response to violence) is suitable. But this still leaves aside the practical question of "what now?"
What do we do. An "intervention" is often confused as a term of art for "sending in troops/bombs/planes/ships" in what could be known as an act of war against whichever force we wish to influence to behave. This is commonly what we mean, but intervening could include diplomatic pressures, economic sanctions, ICC charges for international crimes, financial assistance (or lack thereof), and so on down the line of less violent options of influencing states abroad. Depending on the option and the state, some of these can have an impact. Most will not.
Why is this? Economic sanctions for example are often poorly structured to go after the people in power whose regime is conducting some offending action and often allow that same regime to blame the Americans/Westerners for the misery that is imposed upon the public they govern. Misery coming from the authoritarian regimes activities and the sanctions, the sanctions will take the blame for all of it in many cases and it could actually permit or encourage even more repression that can be gotten away with which normally cannot be. The various other diplomatic and economic pressures like this are often dealing with states with minimal governmental power and social penetration over other non-state actors and thus lacks sufficient control over the territory for which they have border control and cannot contain or deal with international actors meddling or the internal actors attracting international attention demanding international meddling. Indeed, this is often why there's a conflict that we are perceived as wanting to intervene in in the first place is that the nation-state's authority and power is too weak to resolve the situation internally.
Lacking good options, I am not sure what it is that is expected the US is to do over a terrible situation in Nigeria. This seems more like a means and method to symbolically demonstrate our concern. While I share that concern, I do not find the symbolic demonstrating to be all that meaningful as a method of helping. It at least does not seem harmful for Americans to be concerned about and aware of terrible things that go on outside our borders. So go right ahead and be concerned. The likelihood of people looking up Nigeria on wikipedia right now is better than the alternative of people being unaware of what and where Nigeria is.
But don't expect us to be doing much either that will resolve it appropriately and justly. Sending American troops or specialists to extract kidnapped girls in Nigeria is perhaps a heroic action (if it were to work and could be executed), but it does little to resolve the underlying conflicts between the Nigerian government, its people, and the Islamist group Boko Haram that there won't be a future version of outrage, demanding a similarly risky and perhaps even ineffectual response. Arguably it does more to legitimize a terrorising group than help the Nigerian government or its people as a whole. We should be cautious to commit to demands for action by the American nation-state without understanding the circumstances and occasions we are demanding action for.