Hydrostatic equilibrium is a requirement in a stars fusion process, If this expansion is left balanced, you get a stable star, however, if that massive energy release is channeled and directed rather than contained, the resulting pressure ceases to be a structural pillar and becomes a mechanism for Propulsion

When the tension of an electromagnetic field becomes too great, the magnetic field lines cross, fold and break, it is in this electron diffusion region where ions are propelled faster than the speed of light