As the highest possible honor bestowed upon a person posthumously, state funerals are an entitlement offered to a sitting or former President of the United States, a President-elect, as well as other people designated by the President.
McCain did not receive a 'State Funeral,' but he did lie in state at the Capitol, which is not the same thing.
The only non presidents to have received a 'State Funeral' were Thaddeus Stephens, John Pershing, Douglas McArthur and the unknown soldiers of WWII and Korea.
State funerals have been held in Washington D.C. for William Henry Harrison (1841), Zachary Taylor (1850), Abraham Lincoln (1865), Thaddeus Stevens (1868), James A. Garfield (1881), William McKinley (1901), Warren G. Harding (1923), the Unknown Soldier of World War I (1921), William Howard Taft (1930), John J. Pershing (1948), the Unknown Soldiers of World War II and the Korean War (1958), John F. Kennedy (1963), Douglas MacArthur (1964), Herbert Hoover (1964), Dwight D. Eisenhower (1969), Lyndon B. Johnson (1973), Ronald Reagan (2004), Gerald Ford (2006-2007) and George H. W. Bush (2018).
thanks for that. I dug some more. Found the web site for the agency in charge of State Funerals
This has a great description of the “what” - says much of what you are saying.
https://usstatefuneral.mdw.army.mil/docs/default-document-library/faq-sf-general-questions.pdf?sfvrsn=18473e0e_0
also a description of why the military\DOD is involved.
https://usstatefuneral.mdw.army.mil/docs/default-document-library/faq-sf-military-questions.pdf?sfvrsn=a486b034_0
From the same web site... a description of the “hows\why” and history - mostly addresses presidents...
https://usstatefuneral.mdw.army.mil/state-funeral-enduring-home
and descriptions of the cerimonies as it applies to presidents.
I sent an email to I think the right place, asking about Sen. McCain’s funeral status.
From now on, wiki as a quick or last resort. I’ll try to go to the horse’s mouth (or which ever end of the horse is talking that day)
Thanx.