Trump's "first ad wants to scare you into thinking he is the only one who can keep you safe."
The Republican front-runner released his first ad Monday, and its message is that he will keep them out. By them, he means Mexicans and Muslims. The ad is not subtle. It includes images of ISIS fighters, the San Bernardino shooters, and dark figures crossing the border in hordes like an army storming the keep.
The ad is a distillation of the Trump pitch. It’s a bouillon cube of Trump, the one message he wants voters to have in their minds when they go into the voting booth. Campaigns are about creating a need that only one candidate can fulfill. In this case Trump is the protector. Polls show that on the issue of terrorism, GOP voters trust Trump above all others. The ad is not about his ability to make great trade deals or increase wages. He’s going to keep you safe.
So far the GOP candidates have joined Trump in making the presidential campaign about strength against foreign threats. In doing so they have accepted that the contest will take place on the terms Trump finds most advantageous for himself. With less than 30 days to go before the voting begins, Trump would like to keep everyone on that turf and put a wall around it.
http://www.slate.com/articles/news_and_politics/politics/2016/01/donald_trump_s_first_political_ad_wants_to_scare_people_into_thinking_he.html
US vs THEM and FEAR - Trump is a master of the republican playbook.