star trek - Why addict the Jem'Hadar to Ketracel White?

While Richard's answer is excellent, it overlooks one central point in Geewhiz's note.

"When they run out, the Jem'Hadar go ballistic and kill everything in sight uncontrollably."

This is not actually a disadvantage, if accommodated or planned for. Jem Hadar have an incredibly short lifetime (see DS9: To the Death) and mature very quickly, going from infant to Fighting size in a matter of weeks (see DS9: The Abandoned). Given this accelerated life, if a company is compromised from white withdrawal the following strategic points become important:

• The company will self-destruct in a short time frame (DS9: Rocks and Shoals)


• If members of the company are able to survive white withdrawal, they will have trouble subverting others (DS9: Hippocratic Oath)


• The company can be materially replaced quickly. (DS9: The abandoned)


• Direct intervention by a Founder can probably accommodate the situation (Any DS9 showing Founder-Jem Hadar Contact).


• The second, third and fourth items may be combined for an effective, if heartless solution to an insurrection

Given the Founders view all species as subservient, and have a very long term view of strategy, it does not seem that this apparent liability would be viewed as such by them.