Easy ways to understand Trump:

1. his strategy - Spend, Shout, Spend, ...
2. his tactics - go/do A: spend, shout
 - go/do B: spend, shout
 - go/do C: spend, shout
 - etc. etc. etc.
3.his logical plan- none
4. his understanding of issues - none

Why now picking on immigration? No apparent reason; possibly personal feelings, possibly it just happened. There is no obvious reason demographically or politically why this would lead to a GOP presidential nomination.