One of Wall Street's favorite aphorism "This time its different" is frequently used in defense of "deficits don't matter" arguments citing the following pretexts; the US as the world's monetary printing press, safest investment haven, foremost beneficiary to the technological evolution in information and communication among others. Yet, hardly one of these apologists have brought up on why and how such deficits persists....particularly the transformation of liquidity through various innovative 'structured finance' vehicles or instruments. This is entirely the kernel of "this time is different" paragon or what allows the deficits to continue; the transmutation of liquidity.
As to its sustainability and or the ability to subvert business or economic cycles, I put this into doubt primarily because business or economic cycles are primarily driven by base human attributes, namely, greed, hope and fear. For as long as investment decisions are molded out of these human traits, cycles will always hold no matter the technological breakthroughs. To quote Ludwig von Mises in Human Action, "Economics, as a branch of the more general theory of human action, deals with all human action, i.e., with mans purposive aiming at the attainment of ends chosen, whatever these ends may be." Ergo, deficits DO matter and cycles WILL NOT end. Like the fear of the realization of pandemics, these liquidity mutations once stretched to the limits will most possibly end up in tears.