Everyone who says that Steven is being unfair to Jasper needs to stop right now.
Because after poofing the jasper bear, Stevonnie stands back and, rather than pressing the attack on Jasper, says, “Are you ready to apologize now?”
That’s right, even after watching Jasper berate and then poof Amethyst (and prepare to shatter Amethyst as well, probably), Stevonnie gives Jasper the chance to change, or to regroup. It’d be a much better idea to attack Jasper while she’s recovering from that massive hit to her head, but instead Stevonnie asks for an apology. There’s a chance that Jasper will get up and attack them instead, but because they (and specifically, Steven) see the best in everyone, they take the risk.
Jasper gets second chances. She doesn’t take them. Stop comparing her to Lapis and Peridot. Jasper is choosing to fight and to be a bad guy.