Ahhh - but Bush did warn more than just Obama, he warned the leaders of Congress (Obama wasn't even there yet in 2004, if memory serves correctly). Multiple times.
I am certainly not trying to absolve him of the blame, but there were several warnings, they chose to put their heads back in the sand and continue pushing the agenda of allowing banks to make bad loans, with no checks, and then for Fannie and Freddie to cover them.
Kind of like if you had a kid with a gambling problem. Everytime he goes to the casino, and loses money, you cover his debts. He will not learn.
Obama has proposed budgets, you are right. However, he does not seem to want to compromise, nor does he want to push the issue. He could have said three years ago - "pass a budget. I will not continue to sign temporary spending bills without one."