Sorry guys, they screwed up badly and the hostage takers won.
The hostage takers took hostages so that either their demands would be met, or a lot of innocent people were going to die. The goal of any rescue effort is to deny them both.
sure, the details aren't available yet, and we probably should withhold final judgment.
But we can certainly issue an interlocutory and state that deliberately killing over 100 hostages to get to 50-odd terrorists is not a successful outcome. Tey'd probably have killed less by dropping a bomb on the building and charging into the chaos.
Again, this is a hostage situation. In dictatorships, this kind of stunt only works if you take VIPs as hostages. In semi-free countries like the US and Russia, where the media has some ability to incite fear without fear of governmental reprisals, there's no difference between 100 and 600 innocent people dead.
Of course, there is a media difference between terrorists killing them and an HRT gassing them, especially when the hostages are weakened by three days of fasting, medevac is slow arriving, and nobody bothers to tell the doctors what poison the hostages inhaled.