None of This Would Be Happening If Iran Was Not Seeking to Acquire Nuclear Weapons

It is bad enough that Iran already enriches uranium to almost four percent, which requires about two-thirds of the energy required to enrich uranium to ninety-percent weapons grade. Now Iran says it will enrich uranium to twenty percent, which is even closer to weapons grade. Standard nuclear fuel uses four-percent or less enriched uranium. So why is Iran enriching to twenty percent now, with more enrichment later if it does not get its way?

What conceivable motive could Iran have for enriching uranium to twenty percent?