One can only imagine what it is like to be a Republican member of Congress in the age of Trump. What should be a time of harmonious playing, with both houses secure with a GOP majority and a Republican about to assume the presidency, instead is one of jarring orchestration.

The problem is the score written by President-elect Donald Trump. It is discordant and inspires fear among them.

Senate Republicans are not afraid of their leader Mitch McConnell, and their House counterparts do not quake when their leader, Paul Ryan, speaks. But when it comes to the president-elect, there is unspoken fear.

Republicans are not waking to the bright morning of governance, but rather to the “quaking hour” when they find out what Trump did to them overnight by Twitter or some other unplanned communication.

Did Trump ridicule one of them personally, attack a collective Republican action (like the attempt to close the Office of Congressional Ethics) or take aim against a heretofore Republican orthodoxy (like free trade)?

Has he promoted the interest of Russia over the well-grounded suspicions Republicans on Capitol Hill have of Russia in everything, from hacking to aggression in Syria and Ukraine?

Has he offended 27 European countries in the European Union by supporting Britain’s plans to exit?

Has he, perchance, committed the United States to military action on the Korean Peninsula without consulting Congress or our reliable allies in South Korea. Does he know that the South Korean capital, Seoul, lies just 35 miles from the heavily fortified border with North Korea?

There is surely more to come that will cause heartburn with breakfast.

Not all Republicans are climate deniers, even though they may not have liked Democratic prescriptions. Most Republicans are free-traders, and the North American Free Trade Agreement was passed with Republican support. Are they going to be asked to throw in their lot with dismantling it? And what might they get in NAFTA Mark II?

The known points of stress between the Republicans and their leader-elect are now joined — almost nightly — by random pronouncements with huge policy implications.

Trump is exempt from the normal disciplines of politics. He is comfortable with his paranoia, therefore all criticism is the work of “enemies” or fools. He seems to have no icons, no heroes, and no respect for the institutions of U.S. governance or the history that underlies them — hence giving the back of his hand to the intelligence agencies over Russian hacking.

If Trump does not like the message, he trashes the messenger.

This must sit badly but privately with congressional Republicans. They have fought hard over long years to protect the CIA, the NSA and the rest of the intelligence apparatus from being hobbled by the Democrats. So Trump’s cavalier dismissal of their findings must rankle, if not darn right alarm. The links between the intelligence community and leading Republicans are strong and enduring.

Trump will get his honeymoon. Republicans on Capitol Hill will support and explain and excuse the new president. But, in time, there will be a breaking point; a time when the music will change, when Republicans will speak up again for conservative orthodoxy and the going will get rough for Trump.

Tweeting is not governing, and the presidency is not reality television — particularly when you are threatening to upend the world order on midnight caprice.

Beware the quaking hour. It breaks with the first keystroke of the morning, when the GOP finds out what its leader might have done to it and its verities overnight. It breaks for the person who has spoken up and has been ridiculed, singled out as weak.

This is not what was expected from a party winning both houses of Congress and the White House. It is a new dimension in American politics. And the quaking is not just for Republicans.