Donald TrumpWashington (CNN)  Donald Trump shook up America. Now it’s the world’s turn.

The President-elect’s decision to flout 40 years of diplomatic convention and take a call from Taiwanese President Tsai Ing-wen last week suggested he may be just as disrespectful of protocol on the world stage as at home.

The call produced days of speculation about how the President-elect’s impulsive style will reverberate around the globe and whether it could threaten the architecture of international relations.

There are many global traditions and arrangements that he could target, though each could carry a geopolitical or diplomatic price — one reason even presidents who have come into office with all guns blazing often find that there’s a reason why some taboos last so long.

Here are some of the conventions Trump could shake up once he becomes president next month.

  1. Talking to North Korea’s Kim Jong Un – Even Obama, who was willing to engage historic US enemies like Iran and Cuba, has balked at speaking to North Korea’s unpredictable leader, Kim Jong-un. The George W. Bush administration also snubbed Kim’s equally volatile father and predecessor, the late Kim Jong Il. President Bill Clinton did mull a visit to North Korea late in his second term, but eventually decided not to go.
  2. Moving the US Embassy in Israel to Jerusalem – Trump, like his predecessors Clinton and Bush, has voiced support for moving the US Embassy in Israel from Tel Aviv to Jerusalem. It’s an easy vow for a candidate to make, especially since the issue is hugely important to the critical bloc of evangelical voters.  But it’s one of those campaign vows that looks a lot less attractive viewed from the Oval Office.
  3. Human rights as a foreign policy priority – For successive administrations, the cause of human rights has been at the center of American foreign policy.  The issue does wax and wane in importance for different presidents. And there is often debate about whether a certain administration has de-emphasized human rights as a driver of relations with other countries. But human rights campaigners are especially worried about Trump.
  4. Casting doubt on US alliances – For 70 years, US global power and the relative peace and security of the order that America built in the aftermath of World War II have been anchored on alliances. In Europe, NATO has often been referred to as the greatest defensive partnership in history and helped win the Cold War. In Asia, Washington’s partnerships and security guarantees with Japan and South Korea kept the peace in a region now grappling with China’s rise.  But if Trump makes good on some of his campaign rhetoric, those alliances could be in for radical reassessment.
    The President-elect called on South Korea and Japan to pay the United States more for their protection by US troops.
  5. Dropping the careful talk about Islam – The two presidents in office since the September 11 attacks have been highly sensitive to any suggestions that the US war on terror was a war against Islam. Bush visited an Islamic cultural center in the days after 9/11 and Obama flew to Cairo in 2009 to offer “a new beginning” with the Muslim world. Just this week, Obama warned that stigmatizing “good, patriotic Muslims” feeds the narrative of terrorists.