One of the eternal problems of mass communications is the perceived need of appealing to the lowest common denominator. The vote of the most ignorant, mentally limited citizen counts exactly the same as that of the most educated and intelligent citizen.
It is up to the politician to appeal to both.
This is not a huge problem when you are discussing simple concepts, but when the problems and their solutions are complex, then you get the candidates sounding like morons in an effort to find something simple even the most simple minded will agree with.
In England, the style has been for politicians to speak up to the electorate; in America it's always speaking down the electorate, following H.L. Menken's admonition nobody ever went broke underestimating the intelligence of the American public.
These Presidential wannabes want to formulate a zinger or two even the most cognitively challenged citizen can remember, so it becomes: It's all President Obama's fault. He isn't scary enough to the terrorists. All we need is a winner (Trump) a guy who is so tough he scares them (Cruz) not "feckless" (Christie) not a disaster (Rubio) and all the terrorists will run shrieking from the field of battle and stop building bombs in their garages or apartments.
In the case of the San Bernadino shootings: Obama shoulda caught those two. None of the blame can be laid on the Congress, for limiting data gathering after Snowden, and none can be laid on the difficulty of identifying malignant people who are intent on being invisible to whatever radar we might construct.
It's not like the terrorists are robbing banks. Banks you can fortify, and you can arrange for quick response teams alerted by buttons at every teller's station. These terrorists choose places more or less randomly--who woulda thunk a building housing case workers for local health and social workers in San Bernadino?
The fact is, what makes terrorists so difficult to stop is you cannot simply bomb the "shit" out of them because you don't know where they are, and you cannot "carpet bomb them" for the same reason and you cannot simply make the sands glow, attractive as that image may be.
Flexing your muscles and growling in a manly way will not intimidate them or send them fleeing for the doors.
It's interesting: Neither Trump, nor Cruz nor Rubio nor Christie nor any of the tough talkers has ever actually done anything in their lives which requires actual toughness, to my knowledge, like put on a uniform and having a bullet fired at them in anger, or served in a trauma unit handling cases of wounded, or, for that matter, hiked the Appalachian trial, kayaked down the Potomac, run a marathon or completed an Iron Man competition. These flaccid wimps are calling President Obama a weakling.
Certainly Ted Cruz never stood in that White House Situation Room and given the order for Navy Seals in helicopters to attack a compound in Pakistan, knowing full well what happened when Jimmy Carter tried to send in the helicopters across an Arabian desert.
Far as I can see, not a one of them could last ten minutes on a basketball court with Barack Obama. So where do they get all this tough talk?
I remember guys like this from high school and college, who were blow hards, but if you got right in their faces, stood about two inches from their noses and said, "You want a piece of me? I'm right here," well, then they got all jovial and backed off with aplomb born of lots of practice at retreating.
When did we get to the point where nobody calls the bully's bluff in politics?
If we had more prime time Democratic debates, we could have Hillary and Bernie and Martin lacing into the simplicity and saying all the things we want to hear about, but for now, by default, the only voices on the airwaves, the only images are of the thundering herd from behind the podiums.