what two problems must be overcome before fusion can be used to produce energy

before we can harness energy from fusion nuclear reaction , we need  to create a system that can do the following

·       a system that generate the necessary temperature  required for the fusion e.g lasers, microwaves etc.

·       intense pressure to squeeze the atoms until they fuse.  we can use intense magnetic field, ion beams or powerful lasers.

     the atoms are subjected to plasma state where the electrons are strap from the bare nucleus,.  or the atoms are accelerated using particle accelerators to high speed capable of overcoming the coulomb repulsive force .