Population decline is not indefinite. Part of it is due to a collision of historically high standard of living versus the current low economic cycle (historical high living standards meaning that we don't need to have kids to live, while low economic opportunity also makes many of us feel we are not secure enough to have kids or even get married).
You're not thinking of the long game, either. The Japanese too are "moribund", proving that it's a cross-racial phenomenon dependent solely on living standard. This means that as living standards rise around the world, this will become an even phenomenon. First with Asians, then with Latinos, probably Arabs third, Indians fourth, and Africans last.
Monster Hunter: pissing me off since 2010.