the world, by objective measure… …the world has never seen anything like this.

This really weakens the opinion piece, as it attaches a quantitative quality that can easily be attacked. (Two world wars would easily dwarf this)

That said, article goes on to clarify that the numbers and statement are relative to all other conflicts in this century, which is more precise. And most likely factual.

To strengthen the summary, it should clarify that it is comparing to conflicts in this century, although this does make it less sensational.