The world has become familiar with the Green Line, and the Red Line, supposedly a game-changing demarcation.  Now it is likely to become acquainted with the Blue Line, the line devised by the United Nations on June 7, 2000 that demarcates the Israeli-Lebanese border.  This results from events 22 years earlier and the hostilities that began on March 11, 1978, when members of the Palestinian Liberation Organization (PLO) assaulted Israel from their base, which was virtually a state within the state, in Lebanon, killing and wounding a considerable number of Israelis.  In response, Israeli forces invaded three days later and occupied most of southern Lebanon.

Almost immediately, on March 19, 1978, the U.N. Security Council met to pass two Resolutions, 425 and 426, which called for the withdrawal of Israeli forces and created the United Nations Interim Force in Lebanon (UNIFIL). Its mission was to confirm the withdrawal of Israeli forces from Lebanon, help restore peace and security, and to assist the government of Lebanon in "ensuring the return of its effective authority in the area."

As a result of the assassination of the Israeli ambassador to the United Kingdom in London by a PLO group, Israel in June 1982 began Operation Galilee to expel the PLO from southern Lebanon.  UNIFIL stayed behind the Israeli lines, and its role was largely limited to protecting the local population.  By 1985 Israel had withdrawn from most of Lebanon but controlled part of the south, an area manned by a combination of the Israeli Defense Forces (IDF) and the Southern Lebanese Army.  Following the United Nations' invention of the Blue Line in June 2000, a concept respected by both sides, Israel withdrew all its forces later that year.

However, a major consequence of the continuing hostilities was the emergence in Lebanon of Hezb'allah, supported by Iran and Syria, which replaced the PLO as the dominant group in the country. Though Hezb'allah terrorists from Lebanon violated the cease fire and the Blue Line on many occasions the area remained relatively calm until 2006. UNIFIL patrolled the area, observed the movement of troops, kept contact with the different parties, and provided humanitarian assistance.

In July 2006 Hezb'allah invaded Israel, crossing the Blue Line, attacking the area of the Israeli town Zarit, and aiming rockets against other Israeli border towns.  It killed three Israelis, wounded two, and captured two.  Israel retaliated in a conflict that led to deaths of more than 1,200 Lebanese and 165 Israelis.  The role of UNIFIL had to change.  It had engaged in military observations, and provided humanitarian and medical assistance, but also suffered some loss of life and injury.

Its expanded role was created by the U.N. Security Council Resolution 1701 of August 11, 2006, which gave UNIFIL various new functions.  In addition to its original mandate, UNIFIL was to monitor the cessation of hostilities, support the Lebanese armed forces in its deployment through the south of Lebanon, extend humanitarian aid to civilian populations, coordinate its activities with the governments of Lebanon and Israel, and assist  the Lebanese government in establishing an area free of troops and weapons between the Blue Line and the Litani River.  The UNIFIL was to take all necessary action in the areas where its forces were deployed to ensure that the areas were not used for hostile activities.  The number of UNIFIL forces was increased from 2000 to what was supposed to be 15,000, though it never reached that number.

All these U.N. functions were worthy objectives, but the U.N. Security Council disregarded the reality that Hezb'allah, not the official Lebanese government, was now the real power in the country, and was becoming increasingly assertive.  The mandate of UNIFIL was to keep peace between Israel and Lebanon, but Hezb'allah was and is the real opponent not only of Israel, but also of any pluralistic Lebanese government.  It blocked UNIFIL patrols to such an extent that only 10 percent of the patrols included Lebanese troops.  It moved some of its forces south of the Litani River.  UNIFIL has been unable to stop Hezb'allah from acquiring its large arsenal of weapons from Iran.  Furthermore, as Hezb'allah began sending its forces to help the Assad regime in Syria, official Lebanese troops had to be deployed from the south of the country to the north, creating a gap that UNFIL had to fill, and thus making it more difficult to monitor the area.

On May 15, 2013, the UNIFIL base was overrun and three of its troops briefly kidnapped by Hezb'allah, which took arms and equipment.  The result resembled what happened in the United Nations Disengagement Observer Force (UNDOF), which experienced a similar problem of being attacked, leading to withdrawal of Austrian troops from the contingent.  Now, European countries have threatened to remove their troops from UNIFIL unless the security situation improves.  Every country has the right to resign from U.N. forces.  The UNIFIL force is now about 11,000; the European countries, mostly Spain, France, and Italy, which supplied 60 percent in 2006, now account for 30 percent.  The largest contingent in the 38-nation force, comes from Indonesia, which paradoxically does not have diplomatic relations with Israel.

UNIFIL is not the only factor responsible for preserving relative quiet in southern Lebanon, but it is a crucial player in efforts to control hostilities.  It is even more crucial for European nations to recognize the importance of UNIFIL's role and to continue to supply troops.

It would be helpful if the reluctant European Union followed the lead of the United States and finally listed Hezb'allah as the terrorist organization that it is.  It is not a benign political party, and it is meaningless for the EU to try to separate the military wing of Hezb'allah, and call it terrorist, from other parts of the organization.

The fears of the EU are understandable that, if it does designate Hezb'allah a terrorist group, its UNIFIL forces may be attacked.  However, recent history shows that appeasement does not work.  The assassination by Hezb'allah of the Lebanese former prime minister, Rafik Hariri, on February 14, 2005, and the attack on the bus carrying Israeli tourists in Burgas, Bulgaria on July 18, 2012, illustrate that appeasement of Hezb'allah, an organization that embodies a spirit of malevolence and hatred, is unlikely to bring peace and security to Europe or to the Middle East.