What enables ~30k ISIS fighters to compete with ~190k peshmerga, & others?

Question

I was reading this article which includes the following estimates for the numbers of fighters involved in ISIS-related regions:

• Between 7,000 and 30,000 ISIS fighters. Mixed levels of training and motivation, mixed nationalities.
• Up to 190,000 peshmerga. Another article suggests this is an old estimate from 2012 of the total everywhere - but they've received much international support since then, so their current numbers may be higher, with an increasing focus on north Iraq. That article in August 2014 described them as "Increasingly well equipped... motivated, well trained and experienced"
• Around 250,000 in the official Iraq army. They may have performed exceptionally poorly so far, but the numbers advantage is huge.

Not all those peshmerga are involved in this conflict, but ISIS are also divided between many fronts, with other opponents such as the many Islamist splinter groups in Syria, the Syrian army, the FSA, international air forces, etc etc - plus all the difficulties in keeping the cities they have captured in a state of martial law and maintaining supply routes over a wide area.

And then there's also logistical issues getting supplies into the region. There may be plenty of rumours that they are receiving support from wealthy individuals in Saudi Arabia and elsewhere, but there's less of an obvious corridor for them to physically receive this assistance than there is for their opponents who are also receiving assistance from abroad.

So on paper, the numbers really don't look good for ISIS. However, they seem to have been gaining ground as fast as they are losing it, even after the addition of air strikes.

How? What's missing from this analysis that enables them to flourish when the numbers seem stacked against them? And what's stopping them simply being overrun by opponents who have greater numbers, easier access to fresh supplies and (for the Peshmerga) more unified forces with stronger motivation?

Answer 1

This is not a complete answer, just what I gathered so far through the media.

1. IS are equipped with U.S. heavy weapons. This is why Pershmerga got so much more successful when supported by air strikes; the strikes took out the armor, then the lightly armed Peshmerga took out the fighters. We will see how this plays out when Pershmerga fully deploys their German anti tank guns.

2. IS use drugs; this is the same as the WWII German Blitzkrieg. IS fighters are filled to the brim with amphetamines so they can keep going forever, feel less pain, and have less remorse.

3. IS is essentially a death cult; by teaching their fighters that death is a good thing they get them to do dangerous and suicidal things that are good for strategy.

4. The Iraqi army really, really sucks. When IS got started it would be more accurate to describe it as a Ponzi scheme for the benefit of the commanders rather than a real fighting force.

5. IS enjoys considerable popular support because it has been able to position itself as champion of the Sunnis. Iraqi Sunnis had it so bad recently IS rule might actually be a relief.

Answer 2

I think there are two points which you haven't taken into account.

1) The Peshmerga suffered some early defeats during which IS took over portions of Kurdistan. But this was shortly after the Iraqi army had turned tail and run leaving IS armed with fairly sophisticated American weapons. Since then, the Peshmerga have retaken most of the Kurdish territory, assisted by American weaponry and airstrikes, and they seem to be holding it.

2) IS may only have ~30k fighters, but, to quote the NY Times article referenced below, "though ISIS has grown to be the most powerful militant group in Iraq, its foothold in the country relies on negotiating a shifting tangle of smaller groups and alliances." In other words, they have many smaller Sunni militant groups fighting alongside them. These groups are disgruntled with the Shia led government in Iraq. The US demanded that the Iraqis form a 'more inclusive' government before providing assistance precisely to try and bring these groups back into the fold.

[1] :http://www.nytimes.com/interactive/2014/06/12/world/middleeast/the-iraq-isis-conflict-in-maps-photos-and-video.html