The entire world watched 45th U.S. President Donald Trump's inauguration ceremony on Friday. This is proof enough that what the president of the U.S. says and does is important for the entire world. Of course, only the Americans have the power to elect their own president, peoples of the world do not have a say on that. The world knows, however, that Trump who had less votes than his rival but who has somehow won the elections, will take decisions affecting the future of humankind.

That is why his inaugural speech was important, as people around the world tried to understand what kind of decisions he will implement. To be honest, if he is going to run the country according to this speech, we have lots of reasons to worry.

The speech was about conservatism, nationalism and populism. He said he is going to give power back to the people. It does not make sense when you think that all his predecessors in the White House have been elected by the American people, not by the Martians. He probably wanted to say that he is going to fight against different lobbies, civil society and the press. One may say, that is the Americans' business, but if the U.S. adopts an isolationist and nationalist policy line, many other nations around the world will do the same. That is definitely not good news, and after all, Trump may go down in history as the president who caused a world war to break out.

As the president of the U.S. is not only the Americans' business, millions around the world took to the streets over the weekend to protest against him. Women, LGBT people and democrats said "no" to what Trump represents. Before having taken a single decision, Trump, by his existence, is capable of mobilizing millions against him. He is praising nationalism, but at the end, he has helped a global movement.

The U.S. has been presented until now as the beacon of freedom. A country made by immigrants, a place where everyone can become an equal citizen as long as one respects the law. A country where every citizen, regardless their origin, may adopt their own the country's flag, national anthem, and so on. A country where no religious faith has ever been imposed upon anyone.

Almost every country has a majority religion and this helps foreigners to have a vague idea about this country's identity. Sometimes that provokes prejudices, but that's a fact. What was good and different about the U.S. was the religious pluralism of the country. Donald Trump, however, gives little value to pluralism and as George W. Bush did once, he has decided to highlight the country's Christian roots at every opportunity.

He is advocating some kind of American Christianism, a faith that he is going to defend. That's why it seems American Muslims have hard days before them. This attitude will have an impact on American foreign policy as well, and the U.S.'s stance towards Muslim nations. It is at least obvious that Trump will not tolerate any political current or leader using Islamic references.

President Trump has been quick to reverse a number of decisions adopted during the Obama administration, and has chosen to visit the headquarters of the CIA on the first day of his term. He probably knows he has many opponents and that he is not going to spend four quiet years at the White House. In order to counterbalance national and international opposition, he is going to call the U.K., Israel and Russia for help. Maybe he is not going to remain as "national" as he intends to, and the U.S. will be under the influence of foreign leaders.