According to the latest United Nations figures, at least 1,700 children under the age of 10 have so far been killed in the Syrian civil war. This statistic is particularly poignant for those of us who have travelled in and around the now-blighted country and met many members of its predominantly youthful population, but it will also trouble millions of others who have never even been to the Middle East.
There is something uniquely upsetting about infant corpses, especially ones of boys and girls who have died in a war where the total number of deaths is fast approaching 100,000.
Such thoughts were on my mind when, last week, US president Barack Obama suggested that a "red line" had been crossed by the use of chemical weapons in a conflict which has now raged for more than two years.
Mr Obama made it clear that Bashar Al Assad, the Syrian dictator, had now overstepped the mark, and that he would suffer consequences for such behaviour.
At the time of writing, it is not entirely clear what those consequences will be, except that Mr Obama intends to prosecute some kind of limited war by proxy against Mr Al Assad.
The American head of state's sometimes muddled rhetoric rules out direct intervention - a strategy perhaps based on aerial bombardment followed by troops on the ground - but instead implies weapons being shipped to the rebels as a means of tipping the progress of the war in their favour.
This is a hugely risky strategy, and one which could easily escalate matters to more frightening levels. But what is particularly significant about Mr Obama's "red line" is just how long it took the Assad regime to cross it.
The use of sarin - a poisonous gas 500 times more toxic than cyanide - is a vile moral act, and also a blatant breach of international law. Just one milligram of the nerve agent can kill a human being, after first reducing him or her to a quivering, suffocating mass of intense pain.
When, a year ago, I was first shown pictures of 46-year-old Syrian Hassan Abdel-Razzaq's dead family, I experienced as much revulsion as perhaps Mr Obama did when he was presented with alleged scientific proof of the use of sarin.
Mr Abdel-Razzaq had returned to his home in Houla in May 2012 to find his wife, Ghaida, and their five children slaughtered. Safa, his four-month-old daughter, had a bullet in her head, having been shot at close range by militiamen loyal to the Assad regime.
The world reacted with predictable outrage to the massacre at Houla, and there was even talk of the event as a "game-changer". UN secretary general Ban Ki-Moon said Syria could soon go from "tipping point to breaking point".
Mr Abdel-Razzaq, meanwhile, told me to get the photographs of his dead children published, saying: "I wanted the world to see what happened to my family. I also took pictures so that there would be evidence of what had happened."
As it turned out, Russia and China continually blocked attempts to introduce UN sanctions against Syria. Intense fighting not only continued in the country, despite the deployment of some 250 UN observers, but got far worse. More massacres followed, to the extent that they are now barely reported by the international mainstream media.
Instead, Syria was considered a dangerous tinderbox which could spark an all-out regional war if the Assad regime was further provoked.
Russia and Iran are still likely to offer assistance to Mr Al Assad, despite what countries like the US, Britain and France might think of him. So what if the latter do manage to get more weapons to the insurgents? Is flooding the region with even more small arms likely to lead to a rebel victory, let alone any kind of lasting peace?
What is far more probable is that opposing groups in the region will continue to stir up disharmony, bitterly fighting for their own goals, regardless of the long-term threat to peace.
Lebanon's Hizbullah is already backing up Mr Al Assad militarily on the ground, for example. Its alliance is based on numerous factors, including Syrian support for its ongoing campaign against Israel.
The truth is that a child killer like Mr Al Assad will not in the least be worried by claims that he has "crossed a red line".
Civil wars are by far the worst kind, and the sort of mass killings which have been going on are as close to genocide as you can get. Four million Syrians - a fifth of the population - have also been forced to leave their homes, often because they have been destroyed.
Yes, the poison gas has reduced the conflict to new depths of barbarity, but is its alleged use that much worse than babies being shot in the head?
What Mr Obama and his allies have really offered in the face of outrageous war crimes is "red line" jargon - the kind that changes nothing. Instead of prosecutors trying to indict Mr Al Assad and his generals on crimes against humanity at the International Criminal Court, as they should have done months ago, the West presents too many meaningless platitudes.
In the meantime, millions are affected by a civil war which the international community still has next to no will to do anything about.
Nabila Ramdani is an award-winning French-Algerian journalist and broadcaster who specialises in Islamic affairs and the Arab world
On Twitter: @NabilaRamdani