"Interesting that the MP's are going to learn "How to manage that strong reaction"

Well, it's hard to gauge just how "strong" (meaning, pervasive or wide-spread) a negative reaction is these days.  Certainly you can't do it from reading these pages...although we're tempted.  
Kadhr settlement: wow--strong reaction.
PM tweet: welcome to Canada: yikes, very strong reaction.
Think the comment from Billy112 says it: the Liberals have calculated in their tolerance level on rejection.  So, in the Kadhr case, likely weighed the potential and went ahead. 

An uninformed, indifferent, distracted populace means governments are fairly safe. Witness Trump steamroller ability. It's even EASIER than it was, say, half a century ago, because we are no longer as homogeneous a population.  We're all "splinter groups" differing on what we think/fear/want.

It'll take more than one issue or even two to reach a "tipping point."  FN+Kadhr+tweet+tax+ + +.

It also takes something else: a viable alternative.