A method and apparatus for producing soft x-ray laser radiation. A low pressure plasma column is created by electric discharge or by laser excitation inside a rotating containment tube. Rotation of the plasma is induced by viscous drag caused by rotation of the tube, or by magnetically driven rotation of the plasma as it is created in a plasma gun in the presence of an axial magnetic field, or both. A high power electrical discharge is then passed axially through the rotating plasma column to produce a rapidly rising axial current, resulting in z-pinch compression of the rotating plasma column, with resultant stimulated emission of soft x-ray radiation in the axial direction. A rotating containment tube used in combination with magnetically driven rotation of the plasma column results in a concave electron density profile that results in reduced wall ablation and also reduced refraction losses of the soft x-rays.