The only way I could see to defend this is if you have some accelerationist framework where you think that continuing to allow jeets in short term could get you a future where we actually countenance stripping people of their US citizenship, maybe with a paper bag test (fortunately whatever Donald Trump's fake tan is, it's not genetic). Well, that and "third world" is one of those terms where people think they know what you mean, but they don't actually know what you mean, and dishonest actors will exploit such ambiguity.
For anyone who doesn't know what I'm talking about: it's obsolete cold war terminology for geopolitics.
First world: America and other democratic allies, NATO
Second world: commies, i.e. USSR and Warsaw Pact, China, minor allies like Cuba
Third world: unaligned countries, generally poor, who we fought over influencing; e.g. Vietnam, arguably that becomes solidly second world after the war
The danger of using this outdated terminology is that maybe Senator Shitfuck (R KY, Mitch's replacement natch) writes the legislation to implement this, and excludes India on the basis that they were chummy enough with Russia (and big enough socialist retards) through the cold war period that they count as second world, therefore not third world, therefore not what you mean when you were calling to halt third world immigration.