I figured deflectors would be needed, but thought I would throw it out there. Conventional PGS seems to be one of the topics discussed on the web. The use of conventional ballistic missiles could be mistaken for a nuclear launch by Russia or the Chinese. There are other ideas out there such as hyper velocity missiles, but I have not seen lasers discussed as a PGS option. To have the power to reach the other side of the world the laser would require a great deal of power so the system would most likely be gigantic and being space based not feasible. A kind of Death Star but ground based but not destroying planets.