The NRA is arguing (among many, many other things) that the decline in gun homicides over the years proves that no new measures are needed, because Americans are shooting each other less anyway.

They might argue just as cogently that gun laws already in place are responsible for the decline and that more controls will cause an even greater decline. Maybe without laws that NRA lobbied against long ago, the toll would have been higher.

The statistics are evidently true. They do not, however, have a crystal-clear meaning.