As of 2017, the U.S. spends about US$610 billion annually to fund its military forces and Overseas Contingency Operations. Put together, the U.S. constitutes roughly 40 percent of the world's military expenditures. The U.S. Armed Forces has significant capabilities in both defense and power projection due to its large budget, resulting in advanced and powerful technologies which enables a widespread deployment of the force around the world, including around 800 military bases outside the United States. The U.S. Air Force is the world's largest air force, the U.S. Navy is the world's largest navy by tonnage, and the U.S. Navy and the U.S. Marine Corps combined are the world's second largest air arm. In terms of size, the U.S. Coast Guard is the world's 12th largest naval force. 
Military Sealift Command and the Maritime Administration’s sealift fleets are in even worse shape. Combined, they furnish 61 cargo ships. Yet, even that small number is misleadingly high. Twenty-six of those ships run on steam — to call them outdated would be a compliment. We’re also keeping that 61-ship number artificially high by allowing ships to operate for 50 and even 60 years, long past their life expectancy. These older ships require more maintenance and risk major breakdowns.
International protocols restrict the use, or have even created international bans on weapons, notably weapons of mass destruction (WMD). International conventions define what constitutes a war crime, and provides for war crimes prosecution. Individual countries also have elaborate codes of military justice, an example being the United States' Uniform Code of Military Justice that can lead to court martial for military personnel found guilty of war crimes.
What is the military? In simple terms, the U.S. Armed Forces are made up of the five armed service branches: Air Force, Army, Coast Guard, Marine Corps, and Navy. There are three general categories of military people: active duty (full-time soldiers and sailors), reserve & guard forces (usually work a civilian job, but can be called to full-time military duty), and veterans and retirees (past members of the military). And of course there are the millions of family members and friends of military members, past and present. But you're here to learn more about the military. There is much to learn! So first the basics. Exactly who is in charge?
The operational level is at a scale bigger than one where line of sight and the time of day are important, and smaller than the strategic level, where production and politics are considerations. Formations are of the operational level if they are able to conduct operations on their own, and are of sufficient size to be directly handled or have a significant impact at the strategic level. This concept was pioneered by the German army prior to and during the Second World War. At this level, planning and duration of activities takes from one week to a month, and are executed by Field Armies and Army Corps and their naval and air equivalents.
Soldiers and armies have been prominent in popular culture since the beginnings of recorded history. In addition to the countless images of military leaders in heroic poses from antiquity, they have been an enduring source of inspiration in war literature. Not all of this has been entirely complementary, and the military have been lampooned or ridiculed as often as they have been idolised. The classical Greek writer Aristophanes, devoted an entire comedy, Lysistrata, to a strike organised by military wives, where they withhold sex from their husbands to prevent them from going to war.
The rapid growth of movable type in the late 16th century and early 17th century saw an upsurge in private publication. Political pamphlets became popular, often lampooning military leaders for political purposes. A pamphlet directed against Prince Rupert of the Rhine is a typical example. During the 19th century, irreverence towards authority was at its height, and for every elegant military gentleman painted by the master-portraitists of the European courts, for example, Gainsborough, Goya, and Reynolds, there are the sometimes affectionate and sometimes savage caricatures of Rowland and Hogarth.
Examinees also receive a score on what is called the Armed Forces Qualification Test (AFQT). AFQT scores are computed using the Standard Scores from four ASVAB subtests: Arithmetic Reasoning (AR), Mathematics Knowledge (MK), Paragraph Comprehension (PC), and Word Knowledge (WK). AFQT scores are reported as percentiles between 1-99. An AFQT percentile score indicates the percentage of examinees in a reference group that scored at or below that particular score. For current AFQT scores, the reference group is a sample of 18 to 23 year old youth who took the ASVAB as part of a national norming study conducted in 1997. Thus, an AFQT score of 90 indicates that the examinee scored as well as or better than 90% of the nationally-representative sample of 18 to 23 year old youth. An AFQT score of 50 indicates that the examinee scored as well as or better than 50% of the nationally-representative sample.