Strategic Resource: Uranium was deemed a strategic resource vital for the war effort, particularly for the development of nuclear weapons (the Manhattan Project). The U.S. government took control of uranium supplies, effectively preventing its use in commercial products like Vaseline glass.
Security Concerns: The increasing awareness of radiation's potential health risks and the public's heightened fear of radiation after the atomic bombings of Hiroshima and Nagasaki also played a role. Although Vaseline glass is not considered a substantial health risk unless ingested, the prevailing sentiment led to increased scrutiny of anything related to uranium, according to St. James Winery.
Redirection of Resources: The war effort demanded a redirection of resources and materials towards military production, limiting the availability of resources for non-essential goods like decorative glass.
While production of Vaseline glass did resume after the war, it was in limited quantities and with stricter regulations, says Wikipedia.
Again, nice mib Brother