UNITED WE ARE STRONG, UNITED WE WILL WIN" poster
The pattern
This still is filed under Us-versus-them positioning.
Define
The buyer is invited into a side. The product is what we use. The named other is what we refuse.
Mechanism
Identity contrast. Choosing the offer is choosing a group. The out-group does as much work as the claim.
Verdict
The category is crowded
Why it works
The upward angle and scale of the firing cannons convey overwhelming, unstoppable power, while the varied flags clearly communicate that this power comes directly from international cooperation.
Steal this when
You want to reassure an audience by showcasing the massive, combined strength of a coalition or partnership.