Suppose we have a nuke as strong as tsar bomb in space. can we somehow contain the explosion? the same way we contain plasma in fusion reactors.
The fusion reactors currently under development ignite only a microscopically small sample of fuel at a time. The energy release of the tsar bomba was unimaginably bigger (50 megatons TNT equivalent) and despite being detonated 4 km off the ground, its shock wave and thermal blast scoured the ground right down to bedrock and glazed it.
Wikipedia has a good entry about this bomb and after reading it you can safely conclude that there is nothing within human capacity that could be invented to contain a blast of that size in space- or on the ground.