Wood is the material from which the majority of human tools and weapons have been constructed throughout history. In the last few hundred years, natural rubber is quickly claiming a crucial role in the constructions of both peaceful implements and war machines. This is so because wood and rubber have similar physical properties that make them ideal for such a role: hardiness and elasticity. In additions to serving as implements of war, wood and rubber, being extremely important resources, have themselves been at the center of major human conflicts. In the late 19th century and well into the 20th century, struggles for control of tropical territories where rubber-producing plants grow naturally, or can be grown under a plantation system, have played a prominent role in the expansion of European empires and the development of colonialism, with major cost in human life to the local inhabitants and destabilizing global consequences still felt today.