Opportunity cost, the amount of money that is given up in the pursuit of an alternative action, is a cost that does apply to an individual, a business, and a nation. Any time there are choices to be made regarding the finances of an entity, whether that entity is a child with a lemonade stand or the largest economy on the planet, there are costs associated with making financial choices. For example, if the child with the lemonade stand chooses to set up in his or her own front yard because it is safe, it is close to the supplies for making lemonade, and it has a shady tree to put the stand under, the cost associated with this choices may be that the child misses sales of lemonade to potential customers in a higher traffic area or where there are more lemonade seekers available. The benefits of security, closeness to supplies, and a good environment are missed sales.
For a business, there are opportunity costs, both financial and otherwise, with nearly every business decision that is made, regardless of the type of decision. Decisions regarding finances, operations, personnel, marketing, sales, procurement, research, development, and compliance all have benefits and opportunity cost. Some of the opportunity cost is measureable, some is more intrinsic.

The same holds for a nation. Choosing to invest or spend, choosing to raise or lower interest rates, choosing to go to war or not – these are all choices that come with benefits as well as opportunity cost. Tfe difference with a nation is that there are constituents involved who will not agree with the initial choices and will criticize the opportunity cost more so than with a private business or an individual, who may rethink a decision or wish a different decision had been made, but who are not directly responsible to a voting public.