The opposing argument would be that Bush has been too ambitious and in some areas, like foreign policy, he's attempted more than he could have achieved. Reagan was the sort of person who cleaned things up and put the messes of past leaders in order. For many, Bush is one of the mess-makers.
Also, there's a question of how many of Bush's acts will remain in effect. It may be that Reagan influenced the country's history more in indirect and inspirational ways that won't be uprooted or overturned as easily as more overtly political or administrative measures. Beyond that, Bush seems to have been blindsided by events more than Reagan was -- or at least, the consequences of such suprises have been worse.
Most of the time, polls of historians about great Presidents are top-heavy with the leaders the historians agree with politically (polls of ordinary people tend to put the most famous or most charismatic or most recent Presidents on top). But competency and the ability to leave behind lasting achievements matter a lot. Reagan was a much better President than liberals ever thought he was. Time will tell, but Bush may be rated worse than many conservatives think.
I think history will actually be kinder to Bush because many of the ways in which he's tried to re-shape the world will only bear fruit in future years, especially in Iraq. I think Bush will be vindicated on my points in terms of security policy, especially later when Democrats come in to power and tinker with things like the Patriot Act and we end up getting hit again. It will be shown measures Bush took to protect the country were needed afterall.
And I believe despite present difficulties Iraq will down the road be shown to have been a visionary move, one which will spark democractic movements in other countries in the Middle East. We can't see it now because all we see from the media are the carbombs and the blood flowing. But years from now when the media has moved on to some other obsession, Iraq will quietly blossom into a functioning democracy, even if not a Jeffersonian or exactly Western model, one which will inspires others in the Muslim world.
And when the country steadily goes into deeper and deeper debt because we refused to reform Social Security when Bush offered leadership on it and the system slowly goes broke, again history will show Bush's vision was right on the money and at the right time.
As for the things you say Bush was "blindsided by," well I don't think that's entirely fair. Frankly the country has endured more blows to its mainland than ever happened under Reagan including 9-11 and Katrina. That's why comparing Bush to Reagan on that regard really doesn't work since frankly Reagan never dealt with disasters on the scale Bush has had to so we don't know how Reagan's administration would have responded.
But to somehow lay those disasters at Bush's feet and to use that as a measure of his competency is really a brutal standard. It's not Bush's fault our country has been battered by both natural and foreign enemies during these years. And I think he did about the best he could in reacting to them, especially realizing how incompetent the locals in Louisiana were. And let's face it, the media was never going to give Bush his due after the 2004 election again. They resented his re-election and wrote a script long before Katrina that they would focus only on the negative of everything that happened in his second term, rather than focusing on what he did right. Have we heard even one story of what the Feds did well in Katrina? Any credit to Bush for declaring a disaster BEFORE Katrina hit? Any credit to Bush for demanding Blanco and Nagin make a mandatory evacuation order BEFORE Katrina hit when they refused? Any credit to Bush for pre-stationing supplies BEFORE Katrina hit? No, all we here is he flew over NOLA rather than landing and getting in the way of relief efforts and at a time it appeared the city was gripped by lawlessness.
No, history will be very kind to Bush even if our current political and media culture with an agenda of their own are not. Few great leaders have been appreciated in their time. You watch.
You had some good thoughts there and who knows how Bush will be remembered. History is written by the victors. In the case of Reagan, the country has been turning more Conservative over the past 20 years so the victors have portrayed Reagan in a positive light. If the country were to turn more liberal I can imagine history will be written by Michael Moore. Many of his minions certainly troll FreeRepublic these days, don't they?