As soon as he sees Nora grab his niece's arm, Miles knows something is very wrong. His adrenaline spikes and his throat clenches and he has to fight very hard to heed Nora's command to stay back. Part of him is too afraid to move as Nora marks out the other mines, and the other part is so focused on Charlie that he doesn't even register what's going on. He knows he says something to the rebel, but his eyes never leave her. The look of sheer terror in her blue eyes when he approaches is like a knife in his chest. He would give just about anything to be the one with his foot on a bomb. He has to remind himself that Nora knows what she's doing and she's the best hope of getting all of them out of the tunnels alive. He has a hard time counting on other people in any situation, but with Charlie's life at stake, his helplessness makes him want to crawl out of his own skin. A few months ago, he probably would have been the first one out of the tunnel. But now, when Nora tells them to run and the bomb blast knocks them to the ground, he never lets go of Charlie. And somewhere deep in his subconscious, Miles knows he will never let go of that girl.
When Miles hallucinates Bass, he has to confront a fear that he's been fighting with since he realized they were going to take his best friend on. Yes, there were a number of times over the last few years where he had regretted defecting. It's so much easier to be on top. He misses having a sense of purpose in his life, misses walking down a street and having everyone stop and stare at General Miles Matheson, misses being the second-most important person in the republic. More than anything, he misses Bass. Or at least the Bass he grew up with, before the power and paranoia got to him.
When he's particularly down on himself, he thinks that he just might go back. He tries to reason that what he misses isn't there anymore. Bass will never trust him again. They will never be the partners they were, leading the republic into a glorious new era. No, he ruined their friendship when he held a gun to Bass's head.
If it had just been his reasoning stopping him, Miles would never trust himself to resist the lure of the militia. But now, he has something else. He has Charlie, and if all goes well, he'll have Nora and Danny too. That's why he's grateful it's his niece who's standing there when he returns to reality. When he looks down into her big blue eyes he sees his new purpose. It's more than the fact that he made her a promise and he isn't about to go back on his word now. It's more than doing what his brother would want him to do. It's because he loves that girl—more than he realized was possible—and they need each other. So when she tells him to get it together, he silently promises that he will hold himself together for as long as she needs him too.
That promise almost goes out the window when that militia spy's gun goes off. He thinks his heart actually stops when she falls. Miles has had his fair share of life threatening experiences but none even begin to compare to the sheer terror he feels then. It's only been a few months since Charlie came back into his life, but the thought of her being gone forever has him on the edge of a panic. He doesn't think he'll be able to cope if she doesn't open her eyes. He doesn't care if she gets him killed, he'll risk his life a thousand times over if she'll just open her eyes.
His heart begins to beat again and he almost cries from relief when the first flash of blue shows between her lashes. If he weren't too afraid to move her, he would pull her into his arms. Instead he lets go of a breath he didn't realize he was holding and looks away, trying hard to hold himself together like he promised.
Later, Miles realizes that part of him was terrified of Charlie not waking up because he knows that if she hadn't, he would have torn this republic down with his bare hands. He would have put a knife in his best friend's heart for taking her away and wouldn't have thought twice about it. He thinks of his blood-soaked past and realizes that if she hadn't opened her eyes, Charlie's blood would have been the first of so many more that would stain his future.
He hears her shift in her spot by the wall and looks over. Her head is still bleeding a bit and she's fidgeting, clearly not pleased that every time she tries to stand up he gives her a pointed look that sends her back to the floor. She feels his eyes on her and gives him a weak smile, trying to reassure him that she isn't about to black out again. He tries to smile back, but the fear of what's coming stops him. He doesn't want to think about the very real possibility that she may not survive the next 24 hours. Nor does he want to consider the possibility that he may still lose her if she learns the truth about the things he's done.