If the ragheads take things to the next level and perpetrate some sort of small scale but horrific attack on something like a schoolyard playground and wipe out a kindergarten or maybe blow up a bus full of people in a city somewhere and it is determined to be originating out of Mexico things are going to come unglued.
There will be vigilante justice served upon the Arab/Muslim population in the U.S. and also at Mexicans in the U.S. too.
The government won't need their silly threat level yellow, threat level orange B.S. because it will be go-time. They won't need to tell people that or how severe the threat is. It will awaken a sleeping giant. My worry is that the reaction from the government will be directed at the American people mainly, gun confiscations, etc. and focused on looking for terrorists, well, not so much.
Anyone implicated in taking up arms will be immediately branded as "militia" and we have all been conditioned to know what that means. They are the enemy and the "problem" that must be eradicated.
Terrorist attacks taking place in the U.S. of the type Israel has been accustomed to living with for decades, suicide bombers in crowds, car bombs, etc. would IMHO do more than cause the usual terror associated with such attacks. This country is already so divided on so many levels that it may serve to touch off riots on a huge scale from coast to coast. The powder keg is already there, all it needs is the spark.
I've been saying it for years, we will pay dearly for not effectively securing our southern border.