What will replace the ISS after 2024?

There will be Opsek, the Orbital Piloted Assembly and Experiment Complex. It just won't be international, it will be Russian. It will also be to assemble a spaceship for Mars.

NASA's plans are Nautilus-X and recently the Deep Space Habitat which uses the same module design as the ISS.

Note that the Russian concept is basically detaching their section of the ISS before the US plunges it into an ocean if they can since they have no craft capable of moving the ISS currently.

I'd like to say a fully robotic space station, since it is very clear that humans are close to useless in space.

However we already have myriad robotic spacecraft in orbit such as the any replacements for the various comms satellites, landsats, and global positioning satellites. so it is more than probable that the ISS will be turned into a submarine after which we can start applying funding to some real scientific research.

Cheers

If it's decommissioned and deorbited, nothing will replace it. The Chinese are building their own space station, but they're keeping it for themselves.

Hopefully by 2024 American will have gotten our heads out of our asses and started investing in space travel again. That will also require a democratic majority in both houses for at least 10 years.

For that answer, we have to know what will be the future of space flight. They have pondered things from a moon base, to building a station between the earth and the moon and even pulling an asteroid to within orbit. So, we really need to fixate on what our prime destination/ s are. Right now, Mars is gaining a lot of hype and I wouldn't be opposed, but it would probably more practical to first consider constructing a moon base.

I suspect it won't be replaced and won't be decommissioned, but instead will be extended again after 2024.

If that (that is; When) thing comes down.. you might want to beef up your roof.