HemNorth is certainly not the only gardener to raise this question.
One distinction between the two...................
Ornithogalum umbellatum [Star of Bethlehem]: native to eastern Europe and parts of the Middle East
Nothoscordum bivalve: native to the southeastern and south-central United States. Its range also extends into South America.
Second distinction between the two...................................
"The Star-of-Bethlehem is a surprisingly aggressive little plant with attractive flowers. Key features include the spreading racemes of erect flowers, and the triangular or lanceolate filaments underneath the anthers. These filaments are erect and surround the pistil. Other members of the Lily family that are somewhat similar in appearance include the Allium spp. (Onions) and Nothoscordum bivalve (False Garlic). However, False Garlic and the various species of Onions have umbels of flowers and the filaments of their flowers are thread-like."
Taken from 'Weedy Wildflowers of Illinois'
https://www.illinoiswildflower...