Obama forgets that the Constitution is for the people of the United States. Sounds to me that a lot of people forget that these days.
The Constitution is also for those we allow into this country. A Brit is as protected by it as you if he is here legally. Our laws are written to over citizens and non-citizens alike and they must be in a civilized country.
Now if you come here illegally or to kill us the Constitutional protections start to go away but are not entirely absent.