Jack.
Aaron Hotchner couldn't stop thinking about his son. Haley doubted he was a fit husband and father, and while he hated to admit it, she was probably right. Married to the job as he was… But he was Jack's father, and he'd never stopped loving Haley, not for one moment. What sort of protector was he if he didn't try to protect the ones he loved the most? It was a minute-by-minute struggle to not pick up the phone and tell them to get the hell out of there.
But he couldn't. He'd taken an oath, to protect every person, every human being, to the best of his not-little ability. That made them all his family. If he used his unique position to protect only the two who meant the most to him, what sort of protector was he?
And more than that. He was the team leader. He had to set the example. He had to draw the line, and stay behind it. He had to be strong, so that everyone else could see what he was risking and know that they could bear up just as well as he, and with far less to lose. He frankly envied the rest of his team, whose families were all well out of it. Except for JJ. He could see her fear for her son, and knew better than anyone else in the BAU what it was like to fear for your child. He wanted to comfort her, to tell her the lie that it was all going to be alright.
But he couldn't. One leak. That's all it would take. One leak and all the little Dutch boys in the world couldn't turn back the flood.
So he told her his most straightforward reasoning, asking her if it was right to use their position to protect just one among the many. He could see in her eyes that she thought him cold and heartless, knew that he was cementing his reputation of having ice water for blood, but if he broke down, his team would lose it, and they would lose all hope of protecting everyone, their families included.
If the price for keeping his team focused outside of themselves, moving forward instead of falling apart, was that he had to come across as a bastard, so be it. He was strong enough to bear the load alone. This was one duty he could not and would not share.
He only hoped, when this was over, that he would be able to hold Jack in his arms and never, never let go.