Clausewitz called war, “politics by other means” and generally I agree with him... with a few caveats.
All war is political. Violence executed on massive levels requires the organization of mass numbers of people. To tie them together they must have a reason, and that reason--even if cultural or religious--is ultimately political.
I go further than Clausewitz. Clausewitz wrote his theory for nation-states and standing armies. To him, warfare was the extension of politics because it began after diplomacy ended. In current military conflicts raging around the globe, diplomacy, fighting, and reconstruction all go on simultaneously. Clearly, warfare is now between groups, not states, and our terminology defining warfare must reflect this.
And the groups waging violence are political. Frankly, in contemporary warfare violent groups can no longer stay apolitical. Politics and warfare go hand and hand. Whether it is a standing army or a transnational terrorist group, each has to use politics--either persuasion or coercion--to coordinate and organize limited resources to achieve a political result. We need to bring Clausewitz into the fourth generation.
The difference between modern, 4th generation war (as characterized the wars in Somailia, Kosovo, Bosnia, Chechnya, Iraq, Afghanistan, and the Mexican drug wars) and the previous generations of war (epitomized by the Civil War, World War I, and World War II) is that large standing armies no longer meet in a decisive battle. Large armies may meet on the field of battle, but that rarely solves the conflict. Warfare continues long after major combat operations conclude. Without the decisive battle, the solution to violent conflict is political.
War has gone from nation states fighting each other to nation-states fighting political groups, ethnic factions, religious affiliations, economic classes, or even individuals fighting each other. Of course, war has always included sub-national actors, but until the Cold War they could never dominate the fight. As America has learned repeatedly in Iraq and Afghanistan, non-government actors can hurt you as easily as another nation can. Though smaller, they will fight for longer and harder. Their motivation is always the same: political ends through violent means. War is political; and once the warfighter understands that, then the key to unlocking the dilemma of contemporary warfare presents itself.
We fight political war.
For Clausewitz, warfare was the extension of politics into a new realm, a transformation of diplomacy into something else. For the insurgent, the counter-insurgent, the revolutionary, or the fourth generation soldier, politics is warfare. Warfare is political.
Calling conflicts political war aids the warfighter at every level. Strategically, leaders must set clear political goals. Wavering on the goals will cost the commander support, or create a politically tenuous situation at home. Operationally, in political war the greatest gains on a battlefield come from securing the support of key leaders and the support of the population. This political support goes much farther than killing or capturing the enemy. Tactically, allowing needless civilian casualties (whether or not your army caused them) is bad politics, and thus ineffective warfare.
The contemporary operating environment can be called all sorts of things, but we prefer political war. Using terms like low intensity, irregular or unconventional cloud the kernel of truth about warfare. Political war describes the root causes of every insurgency, civil war, revolution, or guerilla struggle waged on our planet today better than any other term.