But what is meant by “Realist”?

If we are talking about it in the context of philosophy then……

a. The scholastic doctrine, opposed to nominalism, that universals exist independently of their being thought.

b. The modern philosophical doctrine, opposed to idealism, that physical objects exist independently of their being perceived.

A particular view of the world, or paradigm, defined by the following assumptions: the international realm is anarchic and consists of independent political units called states; states are the primary actors and inherently possess some offensive military capability or power which makes them potentially dangerous to each other; states can never be sure about the intentions of other states; the basic motive driving states is survival or the maintenance of sovereignty; states are instrumentally rational and think strategically about how to survive.

In his speech in Riyadh, President Trump said his administration was adopting “Principled Realism”—capitalized in the official White House version of the speech, as if to make a statement that there is a distinct doctrine being followed, one worthy of the term realism.  Some commentaries seem to have taken him at his word, with the main reference point being a contrast with the two previous U.S. administrations, which, in very different ways, placed greater importance than Trump does on the extent to which liberal democratic values prevail abroad.  The contrast is based more broadly on Trump’s overall lack of concern for human rights overseas.

But slapping away any interest in democracy and human rights does not define realism.  And we certainly have enough experience now with Trump to realize that his declaring he is doing something may have little relationship to what he actually is doing.

Source: Trump Is No Realist « LobeLog

I Think that his ideas in foreign policy are unrealistic…..he disses diplomacy and embraces a larger more power military and he hugs and compliments petty dictators and monarchs……

President Donald Trump has failed to reassure members of the North Atlantic Treaty Organisation (NATO) that the United States was fully committed to the alliance. When pressed about the importance of Article 5 of the NATO charter—which obliges members to ensure collective defence—Trump dithered. No clarity was possible. He wants NATO members to increase military spending. It is something the U.S. needs little prodding to do by itself.

Trump wants the U.S. to spend over $700 billion on its military, which is astronomically higher than any of the other NATO states. The U.S. expenditure is two-thirds of the total the 28 NATO states spent on their militaries. The U.S. spends 3.6 per cent of its gross domestic product (GDP) on the military, almost twice the 2 per cent standard asked of NATO states. The U.S., by itself, is effectively the military arm of the NATO.

Source: Trump Believes in a World Order Based on Brute Force—and Much of Europe Is Surprisingly Willing to Go Along with It | Alternet

Trump has started the US  down a path that it does not need to travel…..and could very well end badly for the country.