Annie,
I have a funny feeling about this. The 1861 UK census lists Isaac Steele living in Nottingham with wife Sarah Ann and four children, including a son James. His birthplace is Lilburn, so it's the right person, and he is a "commercial traveler"—a salesman.
In 1871 he is out of the picture. His wife Sarah is still in Nottingham with the children, a widow, working as a lacemaker. In 1870 my great-grandmother Rose was living with James H. and her sister Elizabeth, and she was a lacemaker. He was a lace salesman. Could he have met and run off with Elizabeth to America, or some variation of that story? Could he have left his wife and children and changed his name? In the late 1860s he was partnered with another man as an importer, perhaps he had already come to the US. Wow, a lot to think about. I haven't found a UK death record for "Isaac" but I will definitely turn my attention to this.
Pam