[Tony notices the way Bucky becomes more alert and attentive, and part of him feels guilty for causing that reaction, even when he knows it's just part of his training. He likes Bucky, and the last thing he really wants to do is change their friendship.]

Well, don't force yourself to choke it down. I just want you to keep an open mind.

The last thing we need is to lose more secrets. But if we avoid everyone, then we'll never see the enemy coming. We can't afford to take that chance.