I think he may not have become President as soon as he did, but he would have
at some time.
So many things come together to make history. Take Boss Platt for instance.
I haven't gotten to 1900 in Grondahl's book yet, but its early chapters touch
on Platt when Roosevelt when in the NY legislature in 1882. He may have been
desperate to get TR out of Albany in 1900, because, among other reasons, he
may have remembered him from then. So while it was the war that may have made
Roosevelt NY governor, it may have been Platt's long memory that helped made
him Vice President.
By the way, a very unsympathetic and harsh - and highly fictionalized -
picture of TR at the time he became Vice President is in Gore Vidal's book, Empire.
An admirer of TR must have a strong stomach - or a strong drink - or both -
when reading it.