Mary = not-safe

In this day and age I’m sure this is been said but, I gotta say,

Sherlock wants John to be safe.  He came back to life to keep him safe because he was not-safe.  Not-safe because of Mary,  

On the tarmac Sherlock and Mary say the equivalent of, ‘take care of him’, and, ‘no’, respectively.  Sherlock says, ‘keep him safe’, and she says, ‘you know he’s not safe with me’.  She’s wearing red: a colour signifying distress and danger (‘red alert’).  

If Sherlock leaves John with Mary, John is not safe.  Mary confirms this.  Her coat confirms this.  Sherlock immediately comes back because, ‘England’, needs him: John needs him.  He’s still in danger.

I realise that this is obvious to a lot of people.  It’s just that this exchange between Sherlock and Mary is often used to show that they’re now, ‘buddy-buddy’, when truly, nothing could be further from the truth,

Of course, this is cleverly hidden in this friendly banter: Mary knows that John likes to have adventures and she’ll keep him, ‘in trouble’, AKA entertained.  And yet, when someone says, ‘will you look after him?’, the expected answer is, ‘I’ll keep him safe’, not, ‘I’ll keep him in trouble’.  Now, this is why it’s, on the surface, a cute, witty thing for her to say: she’s intimating that they both know how John is, he likes danger, he likes adventures, etc.  She’ll take care of John in the custom way that they both know John requires.  

Except, there’s a very real thing going on here where he’s saying, ‘will you keep him safe’, and she’s saying, ‘no’.  As long as he is with Mary, John is not safe, he’s in trouble.