[jandrewrogers]

A practical laser is unlikely to cut through ablative shielding. There are a couple of caveats to this though.

First, asymmetric ablation can destroy hypersonic vehicles extremely quickly. It is a major cause of failure in hypersonic vehicles even when no one is shooting lasers at it. A laser just needs to induce the ablation asymmetry; the physics of hypersonic vehicles will do the rest of the work.

Second, precision terminal guidance systems can't function behind ablative shielding. The terminal guidance system has no protection from high-power lasers.