America's (and the world's) 'economy' will save itself; it always does. There will be necessary and, in some cases, uncomfortable corrections in all regions and in all sectors: Europe first; then America and finally Asia. The 'prize' is measured in jobs. Jobs are essential for general prosperity and social harmony. The 'best' jobs are 
both reasonably secure and well paying. In the first half of the 21st century the best jobs will be in sectors that require a well (not just adequately) educated and flexible workforce. These jobs are not 'location sensitive' they can just as easily be in Canada or China or Chile.
What governments can do is, in no particular order:
1. Make education work better - higher, 
much higher, standards in 
everything, not just maths and science. A 
creative society has a very, very strong arts and humanities base upon which its science and technology rests. Education must be affordable for 
most people - not necessarily 'free,' just affordable. Education is more than a 
right it is a civic duty.
2. Invest in R&D - government 
direct investments should be in 
Research: in chemistry, not chemical engineering; in biology, not bio-technology. Corporations should get tax breaks for investing in 
Development. Our universities are the 'jewel in the (educational) crown' and R&D is 
one of the ways good universities become great. R&D is cheap, but we, Canada, should 
spend invest 
orders of magnitude more than we do now in it.
3. Make 
continuous learning a reality - workers and managers should 
always be being trained for the next job, the next opportunity. Nowhere is this more important than in low level and middle managers - there are, broadly, too many of them because they are inadequately qualified. Fewer 
managers doing more/better work will make everyone more productive.
This will cost money. It should come, first of all, through reductions in 
most social spending, medical care and old age security excepted - for purely political reasons. Education should be the biggest and 
most important component of provincial spending, displacing medical care. That means that new (
private) money must be injected into Canada's national health care system so that tax money can be diverted from medical care to education - where it will do more good. The next source 'of 'new' money is a tax: a carbon tax paid, à la the HST, by the end user - you and me - every time we fill our gas tanks, turn up the thermostat or watch our big-screen TV. Further 'new' money will, eventually, come from a growing economy.
For the USA, specifically, any new money for education and R&D can be found 
only after the national deficit is beaten down to zero and the national debt is reduced to something akin to 25% of GDP:
http://athensboy.wordpress.com/2009/08/30/prez-chills-keeps-change/
And I'm talking the 
real debt, not the 
unfunded liabilities.
By contrast, Canada's debt is 
estimated (in 2010) at 
about (below?) 30% of GDP - not great but close. But Canada's 
total public debt is, probably, closer to 75% of GDP and the USA's (and China's) is probably more like 90 to 110% of GDP, and growing too quickly.