The reason why Laffer didn't mention Japan is because its banking situation is different:
"The lack of credit expansion, even after expansion of the monetary base, is not due to investors expecting that future interest rates will rise, but is instead caused by the enormous amount of bad debt in the banking system that makes banks unwilling to lend (Herbener 1999)."
In the US, the government magically wiped out the bad debts in the banking sector, so there's no real reason why the banks won't lend going forward (and, as we see, ARE lending).
Consumers will continue to borrow if rates are set ridiculously low and they can purchase assets that will inflate higher than the cost of borrowing!
They will also borrow at fixed rates that are low and not worry about interest rates spiking, or use derivatives to control for this (a recipe for disaster).
Basically, we are looking at 1 of 2 outcomes:
1) LONG TERM: Banks keep lending at low rates, consumers keep borrowing. Inflation escalates out of control. Interest rates are FORCED to spike. Borrowers massively default, credit default swaps collapse, banking sector fails.
2) SHORT TERM: Either rates spike early (in anticipation of scenario 1) or banks/consumers realize what's going to unfold and cease lending/borrowing practices prematurely. Deflation, job losses, equity declines ensue. Unemployment climbs enormously.