I'm not sure that it's entirely about gender, except in the sense that girls are often brought up to be kind, caring and considerate of others feelings and the "boys will be boys" idea seems not to encompass these qualities very much. Girls are often expected to be polite, humble and uncomplaining - that can be to their disadvantage sometimes though.
Thatcher wasn't a particularly caring or sensitive person, and didn't seem very concerned about the deaths caused on both sides in the Falklands War. Golda Meir, again did not seem to instill the ideals of care and compassion, and neither did Indira Ghandi. I therefore think it's more about people who are driven by a number of goals which often include: power, influence, money, success, a need for admiration and unquestioning respect, etc. etc. These qualities are more often tolerated (or even encouraged) in boys but some girls are also encouraged to acquire them.
I can quite understand anyone feeling totally overwhelmed by the terrible things that are happening around the world. It's not just Israel and Gaza (though the inhumanity on both sides is almost too awful to contemplate) - and it's not just man made tragedies - so many earthquakes, floods, fires, etc, etc. I don't know how we should deal with these dreadful tragedies. Some say turn the TV off, don't read the papers, etc. etc. but I feel it is important that we are aware of what is going on round the world. Perhaps rationing how much we watch and read is the only answer.
On the Israel Gaza question, this has been an issue ignored for many years. Isn't the United Nations meant to try and bring parties together and bring Israel to account regarding encroaching on land that is not theirs?
I also agree with Franbern regarding the corrosive nature of religion. Many of these atrocities would not occur if it were not for people following often outdated "rules", rather than using their own sense of what is right and what is wrong to determine how they behave towards others.