A hundred years ago, G.K. Chesterton wrote, "Don't ever take a fence down until you know why it was put up". National borders are like fences, and they are there for a purpose: to keep some people out, and to stop some from running away.
Of course, Shengen changed all that. And this is what they got:
July 14, 2016: A truck, driven by a French-Tunisian Mohamed Lahouaiej Bouhlel, plows through Bastille Day revellers in Nice, killing 84 people.
March 22, 2016: Suicide attacks on the Brussels airport and subway kill 32 and injure hundreds. The perpetrators have been closely linked to the group that carried out the attacks in Paris.
Nov. 13, 2015: Islamic State-linked extremists attack the Bataclan concert hall and other sites across Paris, killing 130 people. A key suspect in the attack, 26-year-old Salah Abdeslam, is arrested in Brussels on March 18, 2016.
Feb. 14, 2015: A gunman kills Danish filmmaker Finn Noergaard and wounds three police officers in Copenhagen. A day later the gunman, Omar El-Hussein, attacks a synagogue, killing a Jewish guard and wounding two police officers before being shot dead.
Jan. 7-9, 2015: A gun assault on the Paris offices of the satirical magazine Charlie Hebdo and an attack on a kosher grocery store kills 17 people. Al-Qaida in the Arabian Peninsula claims responsibility for the attack, saying it was in revenge for Charlie Hebdo's depictions of the Prophet Muhammad.
May 24, 2014: Four people are killed at the Jewish Museum in Brussels by an intruder with a Kalashnikov. The accused is a former French fighter linked to the Islamic State group in Syria.
May 22, 2013: Two al-Qaida-inspired extremists run down British soldier Lee Rigby in a London street, then stab and hack him to death.
March 2012: A gunman, French-Algerian Mohammed Merah who claims to have links to al-Qaida, kills three Jewish schoolchildren, a rabbi and three paratroopers in Toulouse, southern France.
Nov. 2, 2011: The offices of Charlie Hebdo in Paris are firebombed after the satirical magazine runs a cover featuring a caricature of the Prophet Muhammad. No one is injured.
July 22, 2011: Anti-Muslim extremist Anders Behring Breivik plants a bomb in Oslo then launches a shooting massacre on a youth camp on Norway's Utoya island, killing 77 people, many of them teenagers.
March 2, 2011: Islamic extremist Arid Uka shoots dead two U.S. airmen and injures two others at Frankfurt airport after apparently being inspired by a fake internet video purporting to show American atrocities in Afghanistan.
July 7, 2005: 52 commuters are killed in London when four al Qaida-inspired suicide bombers blow themselves up on three subway trains and a bus.
March 11, 2004: Bombs on four Madrid commuter trains in the morning rush hour kill 191 people.
When will Europe wake up and put up its borders again?
As Ronald Reagan said, "A nation that cannot control its borders is not a nation". And Ronald Reagan's second coming, good ol' Donald, trumped it more recently when he said, "A nation without borders is not a nation at all".
