The President, Secretary of Defense and other senior executive officials are advised by a seven-member Joint Chiefs of Staff, which is headed by the Chairman of the Joint Chiefs of Staff, the highest-ranking officer in the United States military and the Vice Chairman of the Joint Chiefs of Staff.[18] The rest of the body is composed of the heads of each of the DoD's service branches (the Chief of Staff of the Army, the Chief of Naval Operations, the Commandant of the Marine Corps and the Chief of Staff of the Air Force) as well as the Chief of the National Guard Bureau. Although commanding one of the five military branches, the Commandant of the Coast Guard is not a member of the Joint Chiefs of Staff. Despite being composed of the highest-ranking officers in each of the respective branches, the Joint Chiefs of Staff does not possess operational command authority. Rather, the Goldwater-Nichols Act charges them only with advisory power.[19]
In broad usage, the terms "armed forces" and "military" are often treated as synonymous, although in technical usage a distinction is sometimes made in which a country's armed forces may include both its military and other paramilitary forces. Armed force is the use of armed forces to achieve political objectives. There are various forms of irregular military forces, not belonging to a recognized state; though they share many attributes with regular military forces, they are less often referred to as simply "military".
When you are considered a career in the military you need to take the ASVAB test. But each branch of the military has different ASVAB requirements that you need to meet. They are different levels of education that you must reach to take the test. But you also need to score a certain amount of points on that ASVAB test to gain access into the branch you desire.
The human capital shortage may be worse than the shortage in ships. A report by the Maritime Administration to Congress highlighted the problem. The report “estimates that 11,768 qualified mariners ... are available to crew the Ready Reserve Force ... the estimated demand for mariners [in an emergency] is 13,607.” Given the shortage, those mariners who are available “may have to endure prolonged assignments or tours of duty until the emergency is over,” which will decrease effectiveness, increase errors and — of greatest concern — delay deploying the forces necessary to win a large-scale conflict.
This continued in the 19th century, with publications like Punch in the British Empire and Le Père Duchesne in France, poking fun at the military establishment. This extended to media other print also. An enduring example is the Major-General's Song from the Gilbert and Sullivan light opera, The Pirates of Penzance, where a senior army officer is satirised for his enormous fund of irrelevant knowledge.

Taken together, this shortage of ships and qualified mariners is “threaten[ing] our ability to meet national security requirements,” as the outgoing U.S. Transportation Command commander, Gen. Darren McDew, told the Senate Armed Services Committee. Our enemies know that, as capable as our military is, it is a paper tiger if it can’t get to the battlefield on time. The deterrent capability of our military is weakened by our inability to deploy combat-ready forces quickly.
On the Learning Tools website, your options include 10-question ASVAB General Science practice tests. These ask you to use terms in context, define terms, and complete basic math problems. You may also be asked to categorize items and answer questions related to general scientific facts. The ASVAB Math Practice Tests are exercises that challenge your ability to correctly answer word problems based on sales and profit, speed, time, area, and other relational concepts.

The IRT model underlying ASVAB scoring is the three-parameter logistic (3PL) model. The 3PL model represents the probability that an examinee at a given level of ability will respond correctly to an individual item with given characteristics. Specifically, the item characteristics represented in the 3PL model are difficulty, discrimination (i.e., how well the item discriminates among examinees of differing levels of ability), and guessing (i.e., the likelihood that a very low ability examinee would respond correctly simply by guessing).