The idea that rules for war like the Geneva Convention are no less absurd than the old-fashioned practice of fighting in straight lines.

Some arguments for:

• Rules for war will be broken by sides the rule-makers probably don't want to win (those who don't respect rules), giving them an advantage over their rule-following opponents.
• Rules for war will be broken so often it's not worth your time drafting them.

Some arguments against:

• Rules for war make wars less devastating on both winners and loosers.
• Rules for war help drafted troops sleep at night.
• Rules for war should be the default rather than the exception.

One effect of this idea is that wars can be divided into two categories, one more extreme than the other:

1. Those wars fought according to rules
2. Those wars where anything goes

Under what conditions will a war officially (as opposed to random incidents) escalate to Level 2?

The phrase also suggests that All's Fair in Love but since I know of no internationally recognized rules for romantic relationships (see The Rules) it seems much less interesting.