The source for the clients is available.

1. https://github.com/DrKLO/Telegram

2. https://github.com/TelegramMessenger/Telegram-iOS

3. https://github.com/overtake/TelegramSwift

4. https://github.com/telegramdesktop/tdesktop

I feel you are unnecessarily combative in your approach. I was making a general observation on the merits of different sourced encryption algorithms.

I also would like to point out how your false dichotomy leaves no legitimate position when arguing against NSA-approved encryption mechanisms for the general public.

From a security perspective, I don't care if open source is solving the backdoor problem - the use of NSA-approved algorithms is the problem, not the source code availability.

From a civics perspective, I find potentially insecure algorithms that can be broken into by more local governments a lot more problematic than insecure algorithms that have a backdoor for governments far removed from, and ideally antagonistic to, my own if my own government cannot read it. The government of China or Russia is unlikely to abduct me in the night to put me into a black site. My own, or their American "friends", are a lot more likely to do so.

If you have a counter-argument other than another ad hominem, I'm happy to hear it.

If you are worried about being dragged to a "black site" Telegram is giving you a false sense of security. The corporation (and the owners i assume) are long gone from Russia, ironically because it could not operate there and was in danger of being censored or appropriated by the Kremlin (they never do things like that...).

Telegram sits firmly within the western legal system and somehow manages to stay online. Their privacy policy references the British Virgin Islands.