The range of radar is 1100 Km and it's located in middle of Iran, which means this radar monitors roughly 500 Km out of Iran's borders. What 'thousands of miles' are you talking about? This means even a quarter of KSA's territory for example is not covered by this radar. Get your facts right.
And about detecting everything, that's why OTH radars are also used to monitor civilian airlines. But since obviously you didn't know, the path of civilian airliners before entering Iran's air space is pre-determined according to international aviation laws and also there is a clear difference between speed of a civilian airliner and a ballistic missile or jet fighter. Also, since the radar is called an early warning system, it means it'll give you a warning of existence of a flying object, it's up to you analyze location/direction and path of that object and to decide whether it should be considered as a threat or not. No country will give their air space to Israel and all of those currently named by the media have already denied it, including Turkey, Iraq and KSA.
If you call my post stupid, then for God's sake, what do you call this? Wow. You don't even know how most OTH radars work and you don't know they don't send signals directly towards the object, they send it first towards Ionosphere in upper atmosphere and detect the reflection, which means mountain won't be in its way.
Thanks for proving any further discussion about this is pointless. Let's just spare our times and 'waste' it on something more constructive.