Related Rule
Netherlands
Practice Relating to Rule 2. Violence Aimed at Spreading Terror among the Civilian Population
The Military Manual (1993) of the Netherlands states:
Acts or threats of violence whose primary aim is to terrorize the civilian population are prohibited. As a result, so-called terror bombardment as well as any other form of terror attack is prohibited. Threatening therewith is also prohibited. 
Netherlands, Toepassing Humanitair Oorlogsrecht, Voorschift No. 27-412/1, Koninklijke Landmacht, Ministerie van Defensie, 1993, p. V-4, § 4.
The manual repeats this rule with respect to non-international armed conflicts in particular. 
Netherlands, Toepassing Humanitair Oorlogsrecht, Voorschift No. 27-412/1, Koninklijke Landmacht, Ministerie van Defensie, 1993, p. XI-6.
The Military Manual (2005) of the Netherlands states:
Acts of violence or the threat of violence, the main feature of which is to instil fear in the civilian population, are prohibited. What is known as terror bombardment, and any other terror attack, is thus prohibited.
It is also prohibited to threaten with terror attacks. The prohibition is clearly a reaction to the many terror bombardments in the Second World War. It is often claimed, in justification of such bombardments, that they served to break the resistance of the civilian population. Apart from whether a reliable means is chosen, customary law recognizes that military operations should be limited to weakening the military capacity of the adversary. The Iraqi SCUD rocket attacks on Israel in 1991, during the second Gulf War, must also be considered as terror attacks. 
Netherlands, Humanitair Oorlogsrecht: Handleiding, Voorschift No. 27-412, Koninklijke Landmacht, Militair Juridische Dienst, 2005, § 0514.
In its chapter on non-international armed conflict, the manual states: “Acts of terror … are prohibited.” 
Netherlands, Humanitair Oorlogsrecht: Handleiding, Voorschift No. 27-412, Koninklijke Landmacht, Militair Juridische Dienst, 2005, § 1039.
In its chapter on non-international armed conflict, the manual also states:
It is expressly prohibited to carry out the following acts against the civilian population or individual civilians, wounded, sick or prisoners:
- acts of terror
- threatening anyone with the above-mentioned acts or treatment. 
Netherlands, Humanitair Oorlogsrecht: Handleiding, Voorschift No. 27-412, Koninklijke Landmacht, Militair Juridische Dienst, 2005, § 1051.
The Definition of War Crimes Decree (1946) of the Netherlands includes “systematic terrorism” in its list of war crimes. 
Netherlands, Definition of War Crimes Decree, 1946, Article 1.