Here’s some background on Hezballah. Here’s some biographical information on its current leader, Nasrallah.
From Wikipedia comes this introduction to Hezballah:
Hezballah was inspired by the success of the Islamic Revolution in Iran. It was formed by the Ayatollah Khomeini’s followers in the early 80s to spread Shia revolution and to combat Israeli occupation of following the 1982 Lebanon War. Hezballah views Israel as " an illegal usurper entity, which is based falsehoods, massacres, and illusions", and follows a distinct version of Islamic Shia ideology developed by Ayatollah Ruhollah Khomeini, leader of the Islamic Revolution in Iran.
Please note that Hezballah’s raison d’etre was the expulsion of Israel from Lebanon. Recall that Israel withdrew from Lebanon. Note that Hezballah has not disbanded, turned in its arms, or ceased terrorist attacks in Israel. Now the stated reason for the existence of Hezballah is the destruction of the "Jewish State".
Now to Nasrallah.
Nasrallah’s biography explains how he got close to prominent clerics in Lebanon, Iran and Iraq, in particular the Sadr family. In 1975, when he was only 15, Nasrallah joined the ranks of the Lebanese Shi’ite movement Amal – which Hezbollah broke from after its creation in 1982 – led by Musa al-Sadr.
From 1976 to 1978 he was sent to study in Najaf, Iraq, at the famed Shi’ite seminary the Hawze. There he met most of his mentors, starting with Iranian ayatollah Ruhollah Khomeini (leader of the Islamic revolution in Iran in 1979) and also his tutor, ayatollah Mohammed Sadiq al-Sadr (Muqtada al-Sadr’s father). He also was in close contact with Ayatollah Ali al-Sistani (the leading Shi’ite spiritual force in Iraq today).
And finally, he was groomed by future Hezbollah leader Abbas al-Musawi, whom he succeeded after Musawi was killed by the Israelis in 1992. Those two years in Najaf definitely left a huge imprint on Nasrallah’s psyche.
And that’s why, when it was time to help his Shi’ite brothers in Iraq after the US intervention in 2003, and especially Muqtada, Nasrallah responded. Nasrallah, using the 1982 model of what had worked in Lebanon to kick out the multinational force, adapted some of his tactics in Iraq.
Indeed, Iraq in 2006 looks a lot like the Lebanon of 1983. For example, the Iranian man in charge of this whole operation is Hassan Qommi, who had the exact same job … in Beirut in 1982. Qommi helped Hezbollah instructors get to Iraq to train Muqtada’s Mehdi Army, which has staged several high-profile confrontations with US forces, notably at Fallujah.
Starting in 2003, Hezbollah began building up organizational and military apparatuses in Iraq. For instance, that April, Hezbollah opened two offices in the Iraqi cities of Basra and Safwan. The campaign, targeting moderate Iraqi Shi’ite clerics willing to work with the US, was most likely orchestrated by Muqtada and Hezbollah.
Keep in mind that even though Nasrallah greatly respects Sistani, he is totally at odds with him when it comes to fighting the US presence.
Also in 2003-04, Imad Mughniah, the top Hezbollah operative wanted by most Western secret services for his role in most of the attacks perpetrated by Hezbollah, including the bombings of the US Embassy and the US and French barracks in Beirut in 1983, was sighted in Iraq. Syria had most probably facilitated his entry on to Iraqi soil.
Hezbollah also had a specialty in Lebanon in the 1980s, which was kidnapping foreign citizens. Is it a coincidence that it was happening on a daily basis in 2004 in Iraq?
Knowing that Nasrallah called for suicide bombings against the US forces in Iraq, it was just a matter of time until Hezbollah was ready to strike. The connection with Muqtada is total. For proof of Hezbollah’s active participation in the insurgency there are the arrests made in February 2005 by Iraqi authorities of 18 Lebanese Hezbollah fighters taking part in the insurgency.
In a July 11 speech that was really focused on the situation with Israel, Nasrallah made a point of again talking about Iraq. He specifically called for Iraqis to step up their resistance against the US invader. In response, Muqtada offered to send members of his militia to south Lebanon to fight Israel. This is not surprising, since Muqtada declared in 2004 that he was "the striking arm for Hezbollah".
Obviously, Hezbollah as a multinational group cannot be simply reduced to Lebanon and Israel. Its expansion into Iraq fits strategically very well in the plans of its two sponsors: Syria and Iran.
Richard Armitage, former US deputy secretary of state, has said that the United States had a blood debt with Nasrallah’s organization. In light of the fact that Hezbollah was, prior to the September 11 attacks of 2001, the organization that had killed the most Americans, and the likelihood of additional killings of US soldiers in Iraq, now would be a good time to repay the debt.
Things are getting a little clearer now that we can identify patterns, relationships, and leadership. Iran, the leader of the Shia Islamist Revolution, has birthed Hezballah. It has educated the children of the Shia in Lebanon, Iran, and now Iraq. Such a child has turned into Nasrallah. Fighting the good fight in Lebanon, he has also committed to action against the US in Iraq. His mentor and tutor is the vile Muqtada Al-Sadr, with whom the US has been actively fighting since his revolt in April, 2004 in Iraq. Many regard Al-Sadr as the leader of the Shia death squads killing Sunnis whenever and wherever they can be found. Al-Sadr has, incidentally, pledged to send 1,500 of his "best men" to Lebanon to help defeat the IDF.
Now perhaps, it is easier to understand the US position on an Israeli-Hezballah cease fire. It is NOT in our interest, in Iraq and anywhere else for that matter, to allow this group to gain a reprieve in a war that offers the opportunity for the destruction of Hezballah, and the damaging of Iran’s prestige. In Iraq, our fight against Hezballah may serve to "clarify" for the Baathist remnants (Sunni Muslims) the point that pushing us out of Iraq only hastens their slaughter at the hand of their fellow Muslims. If the IDF can beat the stuffing out of Hezballah, it may take some pressure off Iraq.
On the other hand, defeating Iran by defeating its guerrilla army makes the situation even riskier. Does Iran have the chutzpah (I could not resist) to raise the stakes? The answer probably is yes. Thus we should expect to see something terrible happen in the Middle East in the near future.
But, if the UN, the Arab League, and various European states succeed in shaming the US and Israel into a cease fire, through reason or through Hezaballah propaganda regarded as truth in too many European capitals and news rooms, the risk of an escalation is probably delayed for a few years.
But no matter how this current affair ends, the Shia War will not end until one of the combatants is counted out on the mat. And the collateral damage to the neighborhood is going to be extensive.
Update: The Telegraph (UK) as more on the subject here.