Thanos grips Tony by the head, the same way he held Thor aboard The Statesman. Thor had seen him soundly defeat the Hulk; he threw and smashed him effortlessly and he didn't even need to use the Power Stone. He could pop Tony's head as easily as Thor could break open a walnut, and when this registers in Thor's head, he finds that his hand is retreating from Thanos' larger form.

He feels utterly powerless. Thanos made him feel this way before, aboard the Statesman, and he has made him feel it again now. Thor tells himself that he can't show weakness -- that he can't show that he cares; both he and Loki made that mistake and Thanos had exploited that weakness.

But still, Thor's eyes flicker to Tony's limp body for the briefest of moments. He is choking on blood; he can hear it, same as he could hear himself when Thanos dragged him by the carapace. Thor lies to himself, tells himself that Tony will die anyway, that he needs to do something. His hands that had withdrawn so easily from Thanos' body before snap to Stormbreaker's grip. He attempts to dislodge the hammer from Thanos' body so he might strike him down, but finds that it is so firmly burrowed inside his body that it does not move, even when Thor pulls with all of his strength.