It's also the context, the act in Beirut while not any less heinous was an attack in the Dahieh which is a Hezbollah stronghold. https://en.wikipedia.org/wiki/Dahieh The perception in this case is like the horrible almost out war drug cartel violence in Mexico, you can have an incident where 50 people get gunned down in a day and it would be barely get reported, 20,000 people die a year to the current escalated violence and it barely gets reported anywhere. Not to mention that most news is Europe/US centric to begin with, as well as very narrative oriented, one about every 50-100 US drone strikes is actually gets reported, usually as side news, while virtually every Israeli strike doesn't matter if it's Gaza or Syria gets pretty much "front pages" news as far as online news sites go.