But the Guam Daily Post said in an editorial that although the island's residents were used to North Korea's threats, the situation was more precarious today because "a feisty, not-so-cool-headed commander-in-chief lives in the White House now".
Its two large US military bases occupy about one-third of the island.
The naval base dates to 1898, when the US took over Guam from Spain after the Spanish-American War.
Guam is also protected by the THAAD missile defense system.
Keeping up his tough talk from his New Jersey golf resort where he is on a working vacation, Trump warned Kim Jong Un's government to "get their act together" or face extraordinary trouble, and suggested his earlier threat to unleash "fire and fury" on North Korea was too mild.
The plan calls for sending 12 rockets over Japan to crash in the waters about 30 miles from Guam, which is 2,100 miles east of the Korean peninsula.
U.S. satellites are constantly surveying North Korea looking at known missile launch sites and watching for any signs of launches from areas they may not know about.
If U.S. territory is threatened, countermeasures are a no-brainer.
The Asian country warned that it is preparing to fire four missiles over Japan and into the waters around Guam - where some 7,000 USA military personnel reside among the island's population of 160,000 American citizens.
The drill coincides with the four-day "Ulji Freedom Guardian" military manoeuvres on August 21-24, which are held yearly and include joint exercises by the US and South Korean armed forces, as well as drills for emergencies.
While experts estimate the consequences and economic impact of an imminent USA vs North Korea war, some Guamanians are stockpiling essentials to survive while taking shelter if Pyongyang makes good on its promise to strike the island. The 163,000 residents that make up Guam's population, which includes 6,000 US service members, are considered USA citizens.
"I'm pro-military buildup", said resident Gus Aflague, 60, whose grandfather and brother both joined the U.S. Navy, according to the report. Along with a bigger set of manoeuvrs held every spring, the exercises are routinely met by strong condemnation and threats of countermeasures from North Korea.
Because Guam is a USA territory, the US military may launch forces from there without worrying about upsetting a host nation that may object to US actions. "I feel it would be a pretty stupid idea to do that", she said.
The Pacific Command, headquartered in Hawaii, determines if the missile poses a threat to Japan, South Korea, Guam or Hawaii. Aegis destroyers are equipped to intercept missiles in the middle of their trajectory while the land-based Patriot PAC-3 system is created to destroy them as they descend towards their targets.
"Since the subway stations in South Korea have enough depth and strength, we will be able to survive attacks".
For now, officials are instead focused on changing the missile guidelines, which allow Seoul to have ballistic missiles with a flight range capped at 800 km (497 miles), topped with a maximum 500 kg (1,102 pounds) warhead.
"No missile is going to land on Guam", Peterson said Thursday.