Modern weapons are expensive, and they not only protect the rich nations but also stimulate their economies. Moreover, few countries have the privilege to own/produce such arms which is why they are so influential on the world stage. Governments that cannot get the official rights to join in this level have a choice to follow with the few privileged ones or go on their own risking sanctions and economic downturn. Judging any leader for WMD is highly subjective given the current state at which the world stands today.

The present US dictator, who owes the arm producers for their votes, has only justified the arguments of North Korea, Iran and some other nations that are to follow up in their new military programs. The whole rich White House propaganda will probably drive up the stock market a little bit again as well as it will most likely open the door to new international conflicts to invest in further. How far this can go remains to be seen.

The current Chinese and Russian dictators that are racing to catch up with the so fancy American technology are in the situation in which they have to stand up to their "enemies" in order to keep their systems running too. The "fate", which you are refering to, awaits us all equally for the guns of today aren't the guns of yesterday. So, the irony of having invested our efforts and money in something that may kill us looms.

Trump did the right thing in this case. The same fate should await the Chinese or Russians if they use chemical weapons against their "enemies".