Yes it is a bad choice,,,,, Like many other of his appointments.If McMaster was brought up with a weak distorted liberal mindset like you suggest then why would Trump appoint him as his NSA? Do you think it a bad choice?In this day and age the liberal mindset is that it is wrong to call a spade a spade.
McMasters was brought up in that mindset.
Some of his appointments seem to be simply to appease the Republican status quo
Trump appointed McMaster, a career military man, because unlike Harward and Petraeus, McMaster couldn't turn him down. If a serving military officer is appointed, he has no choice but to take the job. Similary, McMaster's Assistant Head of the NSA is also a serving military officer, so these people are both easily confirmed, have already passed security clearance, and can't say "No" to the job, nor can they resign.