Why are there so few other countries as long as the president of the United States is assassinated?

From the founding of the United States 1776 to Trump's administration, 45 presidents were elected, of which 9 were assassinated and 4 were successfully assassinated. The probability of the assassination of the president of the United States is relatively high in all countries in the world, so it is very dangerous to be president in the United States.

When the president of the United States is bound to make a choice, he will inevitably offend some international consortia, opposition parties, gang members or members of other interest groups, and the United States is a free country, especially allowing citizens to hold guns for self-defense. In American gun shops, as long as you have money, you can buy all kinds of guns, which provides a good opportunity for various interest groups offended by the president to buy fanatics or professional assassins to assassinate the president. Lincoln and Kennedy were presidents who were successfully assassinated in American history.

Although Lincoln led the northern people to win the civil war, he announced the abolition of slavery, which greatly violated the interests of the southern planters. Since then, Lincoln announced that he would nationalize the right to issue US dollars and cancel the debts owed by the southern planters in the civil war, which seriously offended the international financial groups behind the southern planters. Many people firmly believe that Lincoln's assassin was bribed and manipulated by international financial groups.

In the 1960s, Kennedy also wanted to nationalize the dominance and distribution rights of currency and get rid of the control of American currency by international bankers. Many people speculate that Kennedy's death was similar to Lincoln's, and it was the cheese of the international financial oligarch that killed him. However, some people think that Kennedy was assassinated because he insisted on ending the Vietnam War quickly, which touched the economic interests of American arms smuggling groups and led them to take revenge crazily. Moreover, the United States became the most powerful country in the world after World War II, and has been pursuing the strategy of external expansion and world domination, making too many enemies, especially in Iraq, North Korea, Libya, Iran and other countries, which led fanatics in these countries to want to assassinate the President of the United States. Moreover, the United States is an immigrant country with fierce ethnic conflicts. Many American presidents have been retaliated by both sides for their policies of supporting or discriminating against blacks.