When is enough, enough ???
We all take precautions to avert or repair obvious problems that might (and probably will) occur in our lives.   As an example of this is why we carry an inflated spare tire in our cars.   It would be very irresponsible to have a flat tire with no way to get back on the road. 
In other words, I'm talking about doping what is necessary to avoid an obvious problem, rather than deal with it after the problem takes place.
In the case of terrorism, we deal with it after it has occurred.   Since we know what group is primarily responsible, why aren't we keeping them out of our country ?   Of course, you all know which people I'm referring to...muslims. 
I know all the liberal and politically correct arguments on their behalf.   The bottom line is that islam is not a religion ans all muslims are obligated to destroy all non-believers.
We, here in the United States have practiced the elimination or denial of entry for specific peoples since the earl days of this country.
1656 - Quakers were not allowed to settle here.
1849 - Catholics were not allowed.
1862 - Lincoln passed the "Coolie Act" to keep the Chinese out.
1882 - Exclusion Act prohibits criminals and anyone that can't support themselves from entering.
1903 - Anarchist Act excludes people based on their political ideology (muslims).
1917 - No Eastern Asians or Pacific Islanders permitted.
1921 - Quota Act keeping out Europeans, Africans, Australians, Persians, Turkish, etc.
1929 - 1936  Mexican "Repatriation Act" forced illegals back into Mexico
1942 - Roosevelt signs Executive Order 9066, placing all Japanese in internment camps.
1942 - 900 Native Alaskans were put in internment camps.
1996 - Clinton signs 897KB to deny all public assistance to illegals.
As you can see, we have laws in place that can put an end to illegal immigration, but stop the threat (soon to be a reality) of islam and its sharia law.
One problem has been the Democrats supporting Obama's Deferred Action, and his Executive Action to prevent deportation.
Why do they come here ?   For free food, shelter, education, medical, housing, etc.   If we stop this, most will go back home and only the criminals will stay.   As far as muslims are to be dealt with...it won't be the first time that we rounded up people that posed a threat to us.
Do we need another 9/11 before we act ?   Look what is happening in Europe.   We're next unless we eradicate all muslims form the United States.   I know, there might be some "good ones" but neither you or I know who they are.   Political correctness and liberal, bleeding hearts have made the islamic invasion possible.   Today, almost every European regrets their humanitarian policy of permitting muslims into their countries.
Bottom line is...first, we must get every muslim out of the United States and not permit any to enter.   Then, the world has to make the decision and act upon it to erase islam from the earth.   This is a hard concept to grasp, but if not done soon, you and I will regret that we didn't do what was necessary in time.