What is it with wedding parties and countries bombing them so frequently in the Middle East? How can this be a mistake?
By now wouldn't the wedding planners add a big, easy to read message viable from any aerial view: "Wedding Party In Progress, Women and Children Present, DO NOT BOMB!"
It's often deliberate. A wedding party is the one time that intelligence agencies can be reasonably sure that a particular individual will be in a given location, long enough in advance to arrange to target him. That the target's family and close friends are likely collateral damage is generally considered a bonus by such agencies - the "reasoning" being that a terrorist's family and close friends are likely in agreement with his political positions.
The idea that the US makes special effort to avoid killing women and children is a comforting myth, not a reality - The people making the decisions have long since decided that a few dead foreign women and children are a small price to pay to defend 'our' women and children from the possibility of being the victims of terrorists. And it seems highly unlikely that Saudi Arabia takes a more humane stance on the matter than the US.
A person who knows himself to be a likely target can make himself very hard to find. But family is important enough to them that they likely will not miss the wedding of a close family member. Perhaps some of them buy into the idea that nobody would be so callous as to bomb women and children at a wedding.
All that said, there is also a tradition in many areas of celebratory gunfire at weddings. A crowd of people firing into the air can look a lot like an attempt to shoot down a drone or strike aircraft. So that's probably also a contributing factor.
But mostly I think it's deliberate. Airstrikes are targeted at weddings for the same basic reason that police turn up at mobster's funerals - it's the one time that you know for sure where to find them and their associates.
