Related Rule
Netherlands
Practice Relating to Rule 8. Definition of Military Objectives
Section A. General
The Military Manual (1993) of the Netherlands states:
The concept of “military objective” is defined:
They are objects which:
- by their nature, location, purpose or use make an effective contribution to military action and
- whose total or partial destruction, capture or neutralization, in the circumstances ruling at the time, offer a definite military advantage.
Three elements of the definition have to be present. First, the objects have “to make an effective contribution to military action”, based on “their nature, location, purpose or use”. In addition, the attack must offer “a definite military advantage” in the circumstances ruling at the time. 
Netherlands, Toepassing Humanitair Oorlogsrecht, Voorschift No. 27-412/1, Koninklijke Landmacht, Ministerie van Defensie, 1993, pp. V-2 and V-3.
The Military Manual (2005) of the Netherlands states: “Attacks are permissible only if directed against military targets, i.e. where total or partial destruction confers clear military advantage on the combatants.” 
Netherlands, Humanitair Oorlogsrecht: Handleiding, Voorschift No. 27-412, Koninklijke Landmacht, Militair Juridische Dienst, 2005, § 0225.
The manual further states:
0508. The term “military objective” is also defined. Military objectives are objects which:
- by their nature, location, purpose or use make an effective contribution to military action and
- whose total or partial destruction, capture or deactivation, in the circumstances ruling at the time, offers a definite military advantage.
0509. Under this definition, which deals with equipment and infrastructure, it must not be forgotten, first, that the armed forces constitute a military objective. This means the combatants who belong to the armed forces, and the equipment used by them (tanks, vehicles, aircraft, etc). A non-combatant, who may not take part in hostilities, but uses a weapon, also forms a military objective.
0511. The circumstances of the time are decisive as to whether an object constitutes a military objective. The definition leaves the necessary discretion to the commanding officer. The Dutch Government, in ratifying AP I [1977 Additional Protocol I], has declared in this connection that military commanders who are responsible for carrying out attacks must base their decisions on their evaluation of the information available to them at the time. The Government has also declared that a given piece of terrain may also form a military objective if it meets the above conditions.
0512. It is possible for objects to be classed, on the one hand, as military while, at the same time, they have a civilian purpose. These are known as mixed objects. Examples are a bridge, which can definitely count as a military objective while at the same time its internal structure carries the energy supply to the civilian population of the region. A television mast may not only serve a civilian purpose but perform a function in the telecommunications network of the armed forces. 
Netherlands, Humanitair Oorlogsrecht: Handleiding, Voorschift No. 27-412, Koninklijke Landmacht, Militair Juridische Dienst, 2005, §§ 0508–0509 and 0511–0512.