Following a "terror incident" at Leytonstone Underground station on Saturday night, people are highlighting how the situation would have differed if the UK operated under the same gun laws as the US.
Three people were reportedly left injured, one seriously, after a man allegedly shouted "this is for Syria" and lashed out at commuters with a knife.
While the attack in itself remains shocking, many have been quick to point out how much worse it could have been if access to firearms was as easy as in America.
Because the difference between one knife and one gun is staggering.
Even Piers Morgan had something sensible to say on the matter.
Meanwhile in the US, the Senate rejected two gun control proposals put forward by Democrats which called for greater background checks in response to the mass shooting in San Bernardino, California (the 355th this year).
Syed Rizwan Farook and Tashfeen Malik - the married couple killed in a standoff with police after an attack which left 15 dead - legally bought guns online, according to an FBI inventory, reviewed by the La Times.
Democratic presidential candidate Bernie Sanders has called for tighter laws.
According to the Washington Post he said:
We need to significantly expand and improve background checks.
We need to renew the assault weapons ban. We need to end the sale of high capacity magazines. We need to make gun trafficking a federal crime and give law enforcement the tools they need to get illegal guns off of the streets.
We need to close the gun show loophole as well as loopholes that allow gun purchasers to buy a gun after the waiting period expires without a completed background check.
And still, the gun control debate still rages on...