The pro-Obama answer is that the young senator is a reformer without parallel, a change-maker and mould-breaker.

ECONOMIST: Barack Obama

Rest assured, a surge for 18 months will open a window of opportunity but without parallel development and a major effort to reform the Afghan Government, the sacrifice will all be for nothing and we will draw down then, having lost much and achieved little more than if we withdraw now.

CENTERFORSECURITYPOLICY: A surge is not enough

The raid is a methodical, room-by-room exercise in deadly aggression that is without parallel as a display of force in recent movies.

NEWYORKER: Dead Reckoning

This would be the watch to wear if you believe that discretion is a virtue without parallel.

WSJ: This Sporting Life

At the same time, China from 1979 to 2009 is a case study without parallel: creating wealth by mirroring some behaviors and values of the people who have the money.

FORBES: Take A Hint From China

The most basic benefit it offers is the ability to improve parallel processing without sucking up a lot of electricity.

FORBES: Cray Claims The Fastest Supercomputing Crown With The NVIDIA-Powered Titan

Mr Carter hopes to enter a second century of composition with unlimited horizons, an achievement almost without parallel in the history of 20th and 21st-century art.

ECONOMIST: Elliott Carter

Bigelow directs with power and precision, and the raid at the end on Abbottabad, conducted by Navy SEALs, is twenty-five minutes of dark, green-tinted movement (as seen through night-vision goggles) a methodical, room-by-room exercise of deadly force without parallel in recent movies.

NEWYORKER: Zero Dark Thirty