When a raiding party from the Islamic State of Iraq and the Levant attacked a Saudi border post last week, it was no mere hit on a desert outpost.
The jihadists were launching an assault on the new, highest-profile attempt by Saudi Arabia to isolate itself from the chaos engulfing its neighbors.
The Saudis are building a 600-mile-long “Great Wall” — a combined fence and ditch — to separate the country from Iraq to the north.
Much of the area on the Iraqi side is now controlled by ISIL, which regards the ultimate capture of Saudi Arabia, home to the “Two Holy Mosques” of Mecca and Medina, as a key goal.
The proposal had been discussed since 2006, at the height of the Iraqi civil war, but work began in September last year after ISIL’s charge through much of the west and north of the country gave it a substantial land border with the Kingdom to the south.
The border zone now includes five layers of fencing with watch towers, night-vision cameras, and radar cameras.
Riyadh also sent an extra 30,000 troops to the area.
It is not the only fence with which Saudi Arabia has chosen to surround itself. Despite the difficulty of access to westerners, the country is relatively open to fellow Muslim nations, particularly during the Hajj season when pilgrims from across the world come to Mecca and Medina.
However, that is changing in recent times.
It has also created a physical barrier along parts of the even longer, 1,000-mile border with Yemen to the south.
The attack last week is the sort of incident the Saudis hope to avoid. Three border guards, including General Oudah al-Belawi, commander of border operations in Saudi Arabia’s northern zone, were killed.
All four attackers also died.