The US Isn't Greece? Ctd

Avent says Leonhardt is missing the point:

On the face of things, the problems are similar: revenues minus spending equals a negative number in both America and Greece. And Mr Leonhardt seems stuck on that similarity.

But the differences are crucial. Greece needs to come up with that 6% right now, in the space of a couple of years, in an environment of negative economic growth, because markets are close to refusing to lend Greece any additional money. America needs to close that 6% gap over the space of several decades, during which time it is likely to grow at a real annual rate of about 2.5%.

Do you see how these situations are different?