What is the difference between a business rule and strategy?

Strategy: The mission statement provides guide line in developing a strategy.
A strategy unveils the road map for achieving the goals or objectives of the business.
It has been designed in broad sense.
It further supplies lines for constructing more specific plans, tactics, processes, polices etc.
Business Rule A business rule is the part of the business policy.
For example, a company has HR policy to provide necessary training to new appointee, but has a rules do not involve in direct hiring of the employees, but in this case get the services of the third party agent.
On the other hand, a business rule may be a norm of the industry, which follows almost all players within the industry.
Let me illustrate it by an example, if the industry norm is to sell goods on30 days credit, then how can you (means an entity) ignore it if works under Going Concern Principle.