They may not be as technologically advanced as most Western systems, but they are still frighteningly effective, after all Turkey used NATO standards and Syria still shot one of their aircraft down.
If the US slows its airstrikes over concern for ground based anti aircraft attacks IS will resume its advances, at present the only thing that has enabled the Kurds to hold or to make limited counterattacks is the airstrikes and the massive confidence boost that the US is now helping them.
If the airstrikes stop, or worse IS move more of those captured tanks into Iraq the Kurds are unlikely to hold. They may be motivated and willing to fight but they are significantly out equipped in this war.
Reports of Kurdish fighters having to buy their own ammunition do nothing to dispel the gloom over the difference between the two forces.
What happens next?
Well the situation is slowly getting worse. Not just in military terms but in the far more damaging areas of perception and reputation.
The west has demonstrating again and again that it is happy to meddle and overthrow governments here and dictators there but the massive deployments of force we saw crushing Saddam are a thing of the past.
This is seen and understood.
The west may create chaos but it is very reluctant to clean up its own mess afterwards. Groups that thrive in this chaos can rise to prominence with little fear of opposition from the west which is war weary, fed up of its own warmongering political class and increasingly looking at budgets and costs to limit involvements.
The west always seems to find the money to bomb some government out of existence but helping to establish a stable and peaceful nation afterwards, nope.
So the likes of IS are able to thrive and grow, Each victory increases their reputation and brings more recruits and more support. They are getting rich by selling Syrian and Iraqi oil to middle men who promptly sell the black gold to the west. Western money is buying weapons and vehicles that end up being used by IS forces to expand yet more.
Each day that passes makes the perception of IS strength greater and makes the perception of western weakness more widespread. The situation in the Ukraine adds to this, it is not Russia that is seen as a toothless old bear, it is the US and the western powers who are now seen as the old lions, to feeble to do anything.
The possibility exists that the Islamic State will become permanent simply because the west is not prepared to clean up its own mess. Boko Haram in Africa have already claimed that they are now an Islamic state, others will follow the example of IS, the Far East will be next.
If Assad falls Syria will either become a part of a permanent Islamic State or collapse into the same chaos as Libya. Either way will be a blood bath. If the Kurdish state falls IS will be on the borders of Turkey. If the remains of Iraq fall IS will be facing Iran. IS is a crusader state, a Jihad of conquest, it is run publicly by fanatics who are following the word of god to carve out an Islamic state and they will slaughter anyone who gets in the way.
Once they have beaten their current enemies the Islamic state will look for new enemies, top of that list will be Iran and Turkey with the Lebanon being a light snack and then Jordan and Saudi Arabia will be next to be converted or else.
The west did much to created this mess and now has no options left but to arm those fighting against IS. Assad will become an ally, Iraq and the Kurdish state will be the more or less permanent front lines. Thousands of fanatics and jihadists will be drawn there, to fight and to die and to learn how to spread terror.
If the west does nothing, does not arm those fighting IS, then they will fall and the Islamic state will spread and grow.
NATO may be huffing and puffing about the Russian brick outhouse but that is just hot air, Turkey is a NATO member. If nothing is done, a year or two from now IS could be attacking Turkey and NATO would have no option but to react, Article five leaves no grounds for confusion, an attack on any NATO member is an attack on ALL NATO members.
A few years from now NATO could be at war in the south.
Will it come to that, perhaps, perhaps not. Things change and politicians change as often as the wind. Last year the West was all for bombing Assad so the rebels could take over Syria, now many of those rebels are IS and we may well end up allied with Assad against them.
Politics makes strange bed fellows, unfortunately those politicians seldom bother to think beyond the now to consider the implications of what they do. There is no simple solution. This war will continue for a decade and the hatred will last two generations.
The west is reduced to deciding what does the least harm, we have destroyed our own peaceful options and reduced the situation to how many or how few fight and die.
We made this mess worse and now we find ourselves unwilling to clean up after ourselves.
My how the mighty have fallen.