Originally Posted by
ssullivan
IAH D was designed to support it as well, and offered transit without visa for years until the feds shut that down after 9/11.
You're talking about 2 different things.
Transit without visa was offered for most Central/Southern Americans, and that is at any US airports. That was terminated soon after 9/11 and TSA.
IAH Terminal E (don't know about D), and perhaps some other terminals in the country, are designed to allow sterile transit. That would allow US airlines to retain "Latin America - Rest of The World" traffic. But the feds say no, so those waiting rooms, etc, remain unused.