What are the reasons for buying weapon systems from other countries?

Question

I was wondering, when reading about Turkey being about to buy a S-400 defense system from Russia, how could they even consider that being an option. I get that global alliances went a bit obscured recently. And also understand that Turkey might have interests in increasing their relation with Russia and might consider this purchase for that reason, and also can understand why the USA absolutely don't like a NATO ally buying such a system from Russia.

But what I don't get, how could Turkey consider such a deal, and in the end this not mean drastic consequences for their NATO membership?

Could one do such a purchase and ensure the software running on such a defense system is not supervising and in given circumstances transmitting that data? If I was Russia, and a NATO member wanted to purchase a military system from me. I hella would make sure to add some hidden extra features to the system for them... Just in case, you know. And when I was USA or Turkey, I would pretty much expect Russia to do that, so from Turkeys point of view, I would not consider buying such a system from someone I might at somepoint have to use the system against (given that was one of the initial purposes the NATO was funded for), except I would intend to take sites to some degree with Russia in such a conflict anyways. So from the USA's view, I can understand the USA being concerned about it and not liking this at all. Especially, cause USA's politicans can think as far as I do as well and might wonder, if Turkey even intends to comply with the duty being promised by being in the NATO in case it would be required at some point.

So my question is, am I seeing this correct? Or are there additional measures being taken when buying weapon-/defense- systems from a country you might at some point have to use these systems against? I mean I don't get how one would trust such a system at all in such circumstances.

Answer 1

You seem to be largely unaware of the circumstance under which this deal was made:

Only three weeks after the coup attempt, President Erdogan paid an official visit to Moscow; during the visit his Russian counterpart expressed that Moscow wanted to supply Turkey with the S-400 – the more advanced offspring of the S-300 (eliminated from T-LORAMIDS due to its prohibitive price). Ankara was receptive: Turkey’s foreign minister stated, “we are forced to cooperate with other partners in buying and selling weapon systems, because there are NATO allies who refuse to sell us air defense systems or share (technology) with us”. By October of the same year, Turkey asked that Russia submit a formal proposal for the S-400. In February 2017, Turkey’s Defense Minister announced that they would buy the S-400. The following month, he revealed Turkey’s decision to use the S-400s as a standalone weapon, and not seek integration with NATO.

Integration with NATO systems was dropped precisely because of potential hacking issues.

As for "phone home" that's largely a non-issue, since Russia can monitor the Turkish airspace well enough even without that.

Will the system be able to fire against Russian air planes? I don't know. But it will probably fire against Turkish airplanes that might try to bomb Erdogan again.

Also, this sale is not without risk for Russia. After selling S-300 to Cyprus, the system ended up in Crete and was then used by Israel to test their capabilities to evade it.

Geopolitical deals like this have trade-offs.

Answer 2

Turkey has been moving away from the U.S. and Europe, diplomatically speaking, for the last 20 years, so things are in a state of flux and have perhaps reached a tipping point. They have the "past" of the U.S. and NATO, and they have the "future" of... well, I'm not sure, but apparently they see Russia as an important part of it.

Yes, buying the Russian system is a massive signal that will bring considerable consequences to Turkey, but since they seem to see themselves moving in that direction, apparently the losses from the U.S. and NATO are worth it.

Regarding Russia tampering with the system, yes, I would expect that they do something to protect their own planes from the system. But that is part of the massiveness of the signal that they are giving the world by buying the system. They think it is more likely that they will be fighting the U.S. and/or NATO than that they will be fighting Russia. If you think about it, that is staggering.

There is a good chance that the Russian system will not work against Russian planes, but it is very good against stealth planes, i.e. U.S. planes (F-22, F-35, etc.) and NATO F-35's. Other countries are developing stealth planes, but it seems pretty clear that this purchase indicates a great deal of hostility to the U.S.

EDIT: Read the article that @Fizz linked in his answer- very good read. There is a lot of context, but it appears that the attempted coup in Turkey played a large role in this. They desperately wanted an air defense system that was effective against U.S.-made planes... but it was aimed at their own planes, rather than those of the U.S. or the rest of NATO.

Answer 3

One simple reason may be - the Russian system was cheaper. A lot cheaper.

Another is that Erdogan is using this purchase to get a better bargaining position with the NATO countries for other reasons, by showing that he's capable of going elsewhere if he doesn't like the deal.

Whether the S400 is effective against stealth aircraft remains to be seen. In theory, it is, but actual combat has a way of separating theory from reality very quickly. Actions in Syria revealed that the IAF had no problem defeating the S300 predecessor.

No, the S400 won't integrate easily with NATO defense systems. The Russians will no doubt want to use that to try to extract information from connected NATO systems, but current NATO defense systems already have extensive measures in place to detect attempts to extract information. In theory, the S400 should only be an information provider, as in relaying radar information to an overall command and control structure. In theory, a modified S400 could try to inject malware into a NATO system, but those systems already have extensive hardening against intrusion.

One other aspect to consider: Russia is highly dependent upon arms sales to get hard currency, especially sophisticated systems such as the MIG31 or S400, neither of which is cheap. Were the S400 to attempt to spy on connected systems, and that attempt to be detected, as it likely would be, that would erode trust by any potential customer towards the sophisticated (and profitable) defense systems that Russia is trying to sell. Why buy it if the Russians can kill it remotely, or use it against you later on?

I seriously doubt the Russians would weaken the S400 against their own aircraft. Too much chance a technically adept opponent could figure that out and use it against them. That simple fact is why modern self guided weapons such as missiles or homing torpedoes have no such 'self help' feature built in.

However... the Russians know their system better than anyone, so they may know how best to avoid it.

Remember also that once the S400 is in place, a political change in Turkey could give NATO complete access to the system. So this is a bit risky for Russia as well. I suspect the Russians sold the S400 as much out of a need for hard currency as anything.