Actually, it was the DEM led Congress that pushed it into the stratosphere. Bush signed it to be sure and is also to blame, but Bush's $500B deficit is NOTHING compared to Obama's $1.5 Trillion per year deficit spending (that he plans to keep over $1 Trillion per year going forward in the foreseeable future)
First, for FY07 and FY08, outlays were at or below the amounts that Bush requested in his budget proposals. Moreover, the year to year increases for FY07, 08 and 09 are in line with the year to year increases from FY03 through FY06. Pretending it was the Democrats that pushed spending higher is incorrect. Second, Bush's FY09 budget proposal resulted in a deficit of $1 Trillion so you're off by about 50% on Bush's deficit. Third, the deficit for FY12 under Obama's budget is reduced to below $1T from FY2013 onward.
While you are correct to say that cutting spending could help alleviate the deficit, it is not going to be enough on its own.... they HAVE to raise taxes if they continue spending. Which is why it is not a presumption to state such. You proclaimed Obama should have spent more which implies an even greater level of deficits than we already saw. Thus tax increases are the only way to pay for such spending given the FACT that we know the Dems (and Reps) have done little to NOTHING to curb spending.
Which is why it's stupid to cut taxes without cutting spending first. Yet, every time a tax cut comes up without accompanying spending cuts, you support it nevertheless.