You'd be surprised by what is out there in "open source" stuff...
Heck it's not like we haven't been educating foriegners for decades... Heck we sent the father of Chinese rocketry back to China after Korea, after he worked in our aerospace and missile development programs for years... it's not like there's not agents or scientists working inside our programs now, committing espionage for foreign powers.
Supposedly everything that makes it into the "open source" literature has been declassified, redacted, sanitized, or passed scrutiny and is either "old news" enough that it is of limited value to whomever might end up with it (hostile foreign power) or been superseded by several levels of state of the art and thus is no longer really relevant to modern systems, designs, and materials...
NASA and its contractors must work within the framework of the ITAR-- International Trafficking of Arms Regulations... which can be QUITE onerous and difficult to deal with... especially when it comes to international cooperation and the employment of international partners, their scientists or technicians, engineers, etc, working hand in hand with their US counterparts on various programs... ITAR can be downright stupid, and most folks realize that it causes as much trouble as any harm it prevents... but until Congress pulls their collective heads out of their collective butts and does something about it, it's the law of the land and the rules the game must be played by...
ITAR can be very capricious and rediculous... for instance, a guy who publishes old studies on his website, including a downloadable version of a poster showing the interior of the Saturn V, got a visit from gubmint agents for possible ITAR violations relating to the poster... they "requested" he take the download off his site until they "reviewed" the situation... he pointed out that he got that exact same poster in the Cape Canaveral gift shop and that they'd been selling them there for YEARS, so they were going to have a heck of a time pulling in all those copies... after a week or two he got a terse note saying that it was okay that he put the download back up... evidently, finding a box full of posters containing the EXACT SAME GRAPHIC as his download convinced them that the image truly was "open source" and didn't fall under ITAR...
The government does a LOT of stupidity like this... while they allow agents to infiltrate the NASA and industry organizations and spy for their clients from the inside, when one gets caught (as the recent Chinese "spy" caught inside NASA) Congress inevitably has a kneejerk reaction and does stupid stuff aimed at "improving security", like shutting down the NASA Technical Resources Server, NTRS... which is full of open source materials that have ALREADY been vetted and approved for release on the internet... most of which has already been there for YEARS and therefore has been copied and distributed SO widely that if anything of a sensitive nature WAS on there, it's LONG GONE by now and out in the world free as a bird, and probably copies of it sitting on Kim Jong Un's bookshelf somewhere... All it REALLY does is make people feel all warm and fuzzy, because the gubmint is "doing something" to "enhance security", which is basically NOTHING AT ALL...
Later! OL JR