Over the past week, the topic of "rolling coal" has caught on across the Interwebs. The term needs no explanation among the diesel enthusiast community, who know the term means putting a good puff of black smoke into the air as a way of asserting your truck's dominance over your rivals -- or as a figurative middle finger to nagging environmentalists that like to wag their fingers at anyone not driving a Prius or Leaf.

The practice of rolling coal seems to have grabbed the attention of the larger web community, with multiple outlets picking up on the trend. Some articles have noted the uptick in Google searches for "rolling coal" since the inauguration of President Barack Obama, under whose administration the Environmental Protection Agency has codified some of the most demanding emissions and fuel-economy standards since the founding of the agency in 1970.

Diesel emissions standards in particular have gotten much stricter under the Obama administration, with virtually all new diesel models sold from 2011 onward requiring diesel exhaust fluid (DEF) to meet federal NOx emissions requirements. Although the crackdown is often pinned on the Obama administration, much of the roadmap for future emissions regulations was codified under the Bush administration.

What do you think about "Rolling Coal"? Is it free expression under the first amendment, or just a sophomoric, irresponsible display of diesel pollution?

Source: Vocativ, Slate.com, Tech Times