I support your plan, and present a proposal for phase two: control and efficiency improvements. The density of the plasma determines the rate of fusion, and is

I support your plan, and present a proposal for phase two: control and efficiency improvements. The density of the plasma determines the rate of fusion, and is itself determined partly by temperature. If we were to reflect a significant fraction of the emitted radiation back, then the plasma and its surrounding gas should expand, reducing pressure on the fusing core. That should in turn reduce the rate of fusion, lowering fuel consumption. In theory, we could even diffuse the entire hydrogen supply into a warm cloud that is not dense enough to fuse at all, and store this until we need more heat. As the system cools, it will contract, eventually reigniting itself. Even if we fail and die, it will still reignite itself, which clearly demonstrates the inherent safety of my proposal.