Nic Robertson is CNN's international diplomatic editor. The opinions expressed in this article belong to the author.

(CNN) For some it was never more than a tryst, a brief tango of convenience -- but for most, their love affair with America grew before they really knew it.

That first Hollywood hero who saves the world in a movie with a schmaltzy tear-jerker close, or a Disney cartoon, coloring book or jigsaw puzzle. It was subliminal, as compelling as an evolutionary tie as one has to one's parents.

Over recent weeks, though, Donald Trump has begun to sever that umbilical cord . His brand of "America First" rhetoric raises the once unimaginable question: Is he -- is America -- still a reliable partner?

In 1989, George H.W. Bush was sworn into the White House after serving as vice president under a Hollywood actor-turned-president, Ronald Reagan.

A year later, Saddam Hussein invaded Kuwait and Bush tested global affinity for America by calling for allies to help kick the dictator out. The 32 countries that joined the US-led coalition varied in military capacity, from Argentina to Sweden to Senegal and Poland.

But today, such levels of support seem far from a certainty.

Trump has made troubling comments on Twitter and television about China and showed an unexplained affinity for Russia and a crushing disregard for the cornerstones of European comfort: NATO and the European Union.

Many of America's traditional allies are now asking the question: What pain lies ahead?

No one knows what to expect next. Decisions are on hold, and it's all happening at a very unsettling time.

Over the past year the world feels like it has shrunk.

It's as if global interconnectivity made a subtle shuffle forward. We knew that we could jump on a plane and be in New York, London or Delhi in a few hours -- but things now feel slightly different. Despite the world being messier and more complicated, everything feels somehow simpler and faster.

Three years of record temperatures, a war in Syria, unraveling European unity, and now Trump tweets that ricochet between capitals. We are all touched by everything, often immediately.

Not so long ago, China ignored much of what it didn't like. Today, Trump's Twiplomacy draws a swift rebuke: "Twitter diplomacy is undesirable," China's state news agency declared.

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He used his tweets to such strong effect during his campaign to divert attention away from thornier issues. He may not be so easily put off using them in office. That's also worrisome.

They've become much as a slingshot might in the hands of a bully. Each tweet delivers a stinging flesh wound, rather than something more serious.

Often he seems to use Twitter just to have the last word -- ask Meryl Streep or Arnold Schwarzenegger.

His style is the antithesis of soft-spoken, unseen, quiet diplomacy. He is calling the global order into question with heavy-handed oversimplification at the very moment it least needs upsetting.

The danger for Trump is that none of his tweets are mortal blows. He's antagonizing, alienating and destabilizing enemies and allies alike. None are going anywhere.

On the global stage, countries and leaders may not be as easily distracted as American voters were from their core concerns. A daily barrage of tweets won't distract them from their goals, be they man-made islands or whom they'll send as ambassador to Washington.

As President, he may find a fresh tweet or two a day doesn't keep the bad news story of yesterday away. In short, he won't be able to control global events the way he has at home, where he had to rally enough supporters first to win the Republican nomination and then a majority in the Electoral College.

The unexpected will happen: a simple terror attack or a complex cascade of catastrophes. Kim Jong Un will kick off when he feels like it; the Chinese will respond the way they want to when they want to. What can 140 characters do to hold that back?

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The legacy of Barack Obama's administration is that the world no longer hangs the way it once did on Uncle Sam's first move. His vacillation over chemical weapons in Syria saw to that.

But between Trump's petulance, his Twitter tirades and his at times bellicose rhetoric -- often to be reversed only hours later -- no one knows what to expect. We are entering uncharted territory.

Twiplomacy may disappear, but it's a tactic manifest of a strategy: distract, dissemble, disengage. The need to fight each battle from the same attacking philosophy won't be gone. It's the burden of a bully to find new blows to land.

Who knows, maybe Trump's style will become the new normal. As every military historian knows, the advent of each military advantage -- be it the long bow or the tank -- proved decisive for victory on the battlefield, albeit for a limited period.

But if he keeps making overseas enemies at the pace he has in recent months, the love affair with America will be strained.

Tensions with Russia, Gulf allies and Israel have been running high for a while. Some of it due to Obama's handling of the Arab Spring, some in reaction to Vladimir Putin's annexation of Crimea and invasion of eastern Ukraine. Most recently, Israeli Prime Minister Benjamin Netanyahu was angered by US pressure over Israeli settlements. That said, the global love for Americans generally remains high -- just witness the love lavished on Obama as he prepares to leave office.

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He arrived at the White House with a rock star aura; he leaves -- despite the stumbles in office -- on a high, respected internationally for his integrity and restraint.

The question now is can Trump shut down the uncertainty that his candidacy created and make sure that America has friends when it needs them. Because whether we like it or not, the space between action and reaction on the global stage is getting shorter.