Similar things were thought of before for Northern Ireland in the 70s but not implemented because it was impractical in that case. http://news.bbc.co.uk/1/hi/no

Similar things were thought of before for Northern Ireland in the 70s but not implemented because it was impractical in that case. http://news.bbc.co.uk/1/hi/northern_ireland/4132635.stm http://news.bbc.co.uk/1/hi/northern_ireland/4132635.stm Wouldnt rule it out entirely especially as a political gesture of doing everything possible when unrest threatens, but not as a very meaningful intervention.