Regardless of your politics, the answer to the question above has to be "of course they are".  For a long time following the day of September 11, 2001, many of us awoke each morning and immediately turned on the early news wondering if anything had happened already that day. Frustrated and disturbed by the attacks that devastated our nation that morning  we were mesmerized by the destruction and the amount of death that was delivered by a group of young Arab Muslim men.  In the days that followed, America learned more and more about what happened that day and who was responsible.  The young men shared a hatred for America that was  a seed planted half way across the world and in their eyes blossomed in America on September 11, 2001.  The 911 hijackers acted out a plan to bring terror to America. They were merely pawns in a game of chess that may last for decades and claim enormous life.  Ours and theirs.  The planners of 911 wanted to let each American know that we are not immune to the suffering that Radical Islam delivers to many other parts of the world.  The hijackers came to America. They lived among us, watched us and waited for the anticipated moment to carry out their plan.  Their clandestine "sleeper" cell awoke on September 11th and changed America from that day forward.  I hate to sound pessimistic but to think that this type of incident is a one time attempt or that it can't happen again is being truly ignorant to the world that we live in.  It is frightening to think that even today, there are individuals living among us as apparently ordinary Americans or immigrants that are in secret planning the next attack on America in one of our major cities.

What Is A Sleeper Cell?

A sleeper cell is a dormant, on standby, group of individuals that were either smuggled in, arrived legally or possibly born in the country that is the point of attack.  The members live among the general population and participates within the guidelines of that society attempting to blend in and to not draw any unwanted attention until the time when the cell is to carry out a terrorist attack.  The Hijackers of 911 were operating as a sleeper cell before they acted that day.  They traveled to Las Vegas and took part in gambling and other acts of vice without drawing attention to their real goals.  The clandestine cell is the essential building block of a terrorist operation. Effective terrorist cells are usually very small and tightly managed, generally comprising three or four people and rarely involving more than ten or twenty. When they get bigger, cells become much more vulnerable to penetration by law enforcement or detection by alert citizens. The 9/11 operation was conducted by four cells composed of about three to five individuals per cell, all of which were led by Mohamed Atta. According to reports only Atta, who was the ring leader knew all the details of the attack.

Why are Sleeper Terrorist Cells hard to Find?

As stated above in the definition of the "sleeper cell" these clandestine groups do not want to be discovered.  They want to blend in any way they can.  They do not want to be seen as secretive or as suspicious.  By nature these groups are deigned to be tough to track and to infiltrate due to their small size. Making it more difficult is catching members that know little about the overall plan other than their role.  In essence you have to capture a cell leader or planner prior to the action phase to actually stop an attack and completely remove the immediate threat.  America has a vast array of peoples within her borders and our lifestyles are so busy that at times we do not talk to our neighbors and co-workers.  We go about our lives not paying attention to our surroundings in public places let alone connecting the dots to be able to recognize a terrorist cell in our midst.  All across America in larger and smaller cities alike ethnic communities have been established and it is hard to spot a terrorist cell in the mix of people.  Illegal immigrants can live their entire life outside the governments scope of detection.   Another reason that it is hard to track and find terrorist sleeper cells is because America has very large and porous borders.  We have 4,000 miles of border to the North with Canada and over 2,000 miles of border to our South with Mexico.  Slipping in and out of America in the past was routine for migrant illegal immigrants.  Post 911 has made our government more observant of our borders but by no way is it guarded.  Thousands illegally cross the barriers daily.  Reports of individuals of middle eastern and Asian descent  paying for safe passage through the holes in the border have grown since 911.  In all reality if this was the way that a terrorism organization wanted to enter America for a future attack it is likely that the next wave would more than likely already be in place.  It is possible that the cell may reside in Canada or Mexico and only cross when it was time to conduct the attack by slipping into the country.   U.S. Government estimates that there are as many twelve million illegal aliens living in the united States.  We have as a nation have been able to live without fear of our open borders.  That type of security is gone.  It is too risky to allow our borders to remain unprotected and open to individuals wanting to illegally enter America to do harm against it's citizens.