As tensions escalate between Trump and North Korea, the threat of war is becoming increasingly real. President Trump’s provocative choice of words only serves to push Pyongyang into launching more missiles, each one flying at a longer distance than earlier rockets. From a short range of 500 kilometers in its February launch, recent ballistic missiles flew at 6,700 kilometers, putting them in the category of intercontinental ballistic missiles (ICBM.)

These are alarming signs that the Democratic People’s Republic of Korea has the nuclear capability to go to war, whether in defense or as the aggressor. Doubts about North Korea’s claims were erased when it tested a hydrogen bomb in early September, and experts say the device had an explosive yield of more than 100 kilotons TNT equivalent, considerably higher than its previous tests.

Is war between the United States and North Korea possible? How can a country that is not more than 121,000 square kilometers big with a population of 25 million fight a Goliath measuring almost 10 million km2 and having more than 323 million people? Here’s what has been happening:

North Korea: We will turn the whole of US into fire.

This is Kim Jong-un’s response to Trump’s threat to “totally destroy” the communist regime in his speech at the United Nations general assembly in New York. Unlike the US president though, Kim’s official says they will fight with fire, not words.

North Korea has one of the largest conventional military forces in the world. Every male Korean over 18 years old is required to serve in the armed forces for ten years. Then in early 2015, Kim made military service for women mandatory as well. Female Koreans must now serve in the armed forces after graduating from middle school, usually at 17 years of age, until they reach the age of 23. At any one time, Pyongyang has between 1.5 million to 6 million reservists it can call on to serve the country. For comparison, the US has a total of 1.4 million active military personnel.

A substantial portion of the country’s budget goes to the military. The US State Department estimates that 22 percent of Pyongyang’s GDP is spent on its military, even as its people suffer from famine.

Brinksmanship is the trademark of North Korea’s nuclear program. It has tested all types of ballistic missiles, from short, medium, intermediate and intercontinental range, capable of reaching the United States. Intelligence reports estimate that the country has between 30 to 60 nuclear weapons and an even more troubling thought is that Kim has presumably developed miniaturized nuclear warheads to fit its missiles.

A Stanford University assessment puts one million people that could be killed on the first day of war between the US and North Korea.

Trump tweeted: Only one thing will work.

Although he didn’t clarify his statement, the thought in most people’s minds is its suggestion of military action. A pair of Air Force B-1 bombers conducting drills off the coasts of the Korean Peninsula further strengthens the idea.

The thought of a US preemptive attack on North Korea is scary, especially for the 25 million people in Seoul and much of Japan. If it’s any consolation, Trump’s Secretary of State Rex Tillerson and Defense Secretary James Mattis have maintained their presence of mind and are open to a dialogue with the rogue leader Kim to arrive at a diplomatic resolution.

But the bigger question is, can the US take out North Korea in a single attack? Will it take out only the nuclear weapons, or will it be total annihilation? A protracted attack will give Kim time to fire back with its 15,000 artillery guns and its short-range ballistic missiles trained on Seoul. Eventually, the US and its key allies South Korea and Japan will win the war, but at a horrendous price. A conservative estimate would be thousands of South Korean, Japanese and Americans living in these countries killed.

North Korea will have as many casualties, and Kim will be overthrown, if he survives an attack. A US-North Korea war will lead to World War 3, with Russia and China on North Korea’s side and South Korea, Japan, and other US-allied nations on the side of America.

What are the chances of Trump initiating a war?

President Trump at heart is a practical person. He knows the deadly consequences of an actual war with North Korea and he will not sacrifice American lives. He will only strike if Kim Jong-un makes the first move of aiming an ICBM or a nuclear warhead at the US mainland or its territories. Experts calculate that such a missile launched from Pyongyang can reach Guam in 18 minutes or New York in 40 minutes.

North Korea is being monitored through various means – satellite imaging, spies, intercepted communication, etc. The second an ICBM is launched from North Korea towards the US, President Trump can give the order to attack with the country’s own missiles. Trump isn’t bragging when he says America’s nuclear weapons are now more powerful and sophisticated. A retaliatory missile can reach North Korea from the US in five minutes and a submarine missile in 15 minutes.

But a missile intercepting another is not as simple as it seems. The continuous rotation of the earth can disrupt trajectory and it takes four missiles to shoot down one. Even then, there’s no surefire guarantee of success.

The biggest provocation, of course, is the name-calling these two bombastic and unbalanced leaders are engaged in. If they were just two drunkards on the street, the heated exchange would turn into a fistfight. But they are presidents of two countries and an order from them can lead to a nuclear disaster that neither had really planned on.