Fusion is irrelevant.

It marginally reduces the size of a fission plant, a non-problem.

It presents klingon level engineering problems.

The feedstock and its subsequent volatility are civilization grade problems.

In the designs I've seen thrown around, you end up generating tritium and helium inside the lithium reactor cover/blanket.

I'm not saying we shouldn't pursue it for research purposes, but the desire to research is politically/emotionally driven and not based on the discovery of any recent phenomena.