I agree with that. Most of this is not on Bush.
However, there is substantial evidence from around the world that financial deregulation leads to excess credit creation and asset bubbles. That doesn't mean deregulation is necessarily bad, but to say it is always good under all circumstances is just ideology.
a lot of decisions by the Bush administration were crucial in causing the meltdown.
If the Bush administration hadn't abdicated basically all lending standards from 2002 onwards there wouldn't have been the vast amount of bad loans written that were written.
If they'd let individual states tackle predatory lenders instead of using the power of the federal government to prevent it, actually using regulatory bodies to prevent regulation, then there wouldn't have been so many bad loans written.
If the SEC hadn't let the five biggest securities firms lever up their debt: assets ratio from 10:1 to as much as 30:1 then maybe all five would still exist and wouldn't have racked up such enormous losses.
And it would have helped if Bush had appointed actual regulators to run the various regulatory bodies instead of ex-banking lobbyists, people who'd spent their careers lobbying Washington to cut banking regulations. This is what happens when you do appoint a banking lobbyist to run a regulatory body. He's the one with the chainsaw :
The government basically just got the hell out of the way in the early 2000s and set the markets free to bring us peeance and freeance and unrivalled prosperity. The Bush administration had pro-growth business-friendly policies which as far as the financial industry went amounted to letting them do what they wanted and even using the power of the government to prevent any action that might slow down the booming mortgage sector.
Take a lot of those bad loans out of the system, specifically all the ones written between 2002-8, and take all the added leverage out of the system then although you have a completely unregulated derivatives market you don't have the raw material to construct those toxic derivatives out of and you don't have the huge risk-taking that the excess leverage allowed and the huge losses that followed.
Though I generally agree with your points, legislation to deregulate G-S and take derivatives out of regulatory oversight came under Clinton, not Bush. That doesn't absolve Bush of all responsibility, but much of this occurred before he came to power, and under areas in which the White House had little or any jurisdiction.
For example, there wasn't much Bush could do about Fannie and Freddie because of the opposition to any reform in Congress. Though the GSEs are not the primary cause of the meltdown, you can't plausibly argue that the GSEs had no effect on the Financial Crisis. It is true that they lost share and played a small part in the subprime debacle, but they were massively overleveraged and were systemic risks to the general economy. Bear, Lehman, et. al. went from leverage of 12:1-15:1 to 30:1-40:1 under the ruling that you cite, but the GSEs were leveraged at 50:1 or higher.
All bubbles are a result of excess creation of credit. So you have to find the sources of credit creation to find the sources of the bubble. The single biggest influence on credit creation in this country is the Federal Reserve. It is they who set the baseline prices for credit in this country. Thus, it is the Federal Reserve which bears most of the responsibility for this debacle by keeping credit too cheap for too long. If you want to blame Bush for reappointing Greenspan, fair enough. But so did Clinton, and his approval sailed through Congress no matter what the party.
So no, Bush and the Republicans do not deserve the majority of the blame for the Financial Crisis. They, like the Democrats, are culpable, but look beyond the political arena and you will see where the true culprits lie.