That was part of the mission profile, no? If it hadn’t been you’d have a point, but as I understand it that was a reasonable milestone to hit and to determine if an animal can even survive for a time in orbit before they risked a human life.

Animals often die in experimentation and that’s usually the whole point of the experiment.

Sure. So you could maybe add the first animals to safely return from space into the list too - the first win on the American side if you're counting sub-orbital flights, otherwise it'd've been Sputnik 5.