Common Article 2 relating to International Armed Conflicts
This article states that the Geneva Conventions apply to all cases of international conflict, where at least one of the warring nations have ratified the Conventions. Primarily:
The Conventions apply to all cases of declared war between signatory nations. This is the original sense of applicability, which predates the 1949 version.
The Conventions apply to all cases of armed conflict between two or more signatory nations, even in the absence of a declaration of war. This language was added in 1949 to accommodate situations that have all the characteristics of war without the existence of a formal declaration of war, such as a police action.[12]
The Conventions apply to a signatory nation even if the opposing nation is not a signatory, but only if the opposing nation "accepts and applies the provisions" of the Conventions.[12]
Article 1 of Protocol I further clarifies that armed conflict against colonial domination and foreign occupation also qualifies as an international conflict.
When the criteria of international conflict have been met, the full protections of the Conventions are considered to apply.
That ougt to have some interesting implications for the Israeli-Palestine conflict - has Hamas accepted and applied the provisions of the conventions? 
One could also quite legitimately ask if Israel is following them, too.
In any case, thanks for the info regarding the convention. The more you know...