They are part of Iran’s effort to build a Shi’a’ bridge from Iran to the Mediterranean. They mar pose more of a threat to Assad, than to Israel. But their presence is nevertheless a danger.
But the idea of 80,000 militiamen on Israel’s border is, as al-Tamimi argues, a bit of an exaggeration.
Some of the fighters exist only on paper and others, like the Afghans, are not well armed and have been used as cannon fodder by the regime. They aren’t equipped to fight an enemy like Israel; rather they’ve been dying in the hundreds fighting Syrian rebels and ISIS. It appears the number of recruits has decreased as their home communities have become reticent to send young men to Iranian recruiters to end up dying in Syria. In the beginning religious devotion and wanting to defend holy shrines in Syria was a motivation. Those shrines are now safe and the jihadist threat that motivated the recruitment drive has been beaten back.
The lasting influence and infrastructure of the Iranian militias will be felt long into the future. Regardless of their exact numbers, they have deeply affected the region and the networks that they carved out, from far off Pakistan to the Golan, are part of Tehran’s quest for hegemony.
https://www.jpost.com/Middle-East/Who-are-Irans-80000-Shiite-fighters-in-Syria-552940