BELFAST — In the 241 years of this republic, two Mainers have made indelible marks on its history. Two Mainers bravely stood up to corrupt thuggery at the highest levels of government. It is time for a third.

Republican Sen. Susan Collins’ role in the health care debate has been principled and courageous. Collins showed real courage in standing up to her party’s effort to throw 23 million off health care and give 40 percent of the proceeds to the 1 percent. She held her ground. She refused to vote for legislation that would devastate Maine. Bravo.

During Senate debate, Sen. Jack Reed, D-R.I., was caught on microphone telling Collins he thought President Trump was “crazy,” to which Collins replied, “I’m worried.”

Collins is right to be worried, but that’s not enough.

In the 1950s, Sen. Joseph McCarthy’s vicious anti-communist witch hunt was destroying lives, poisoning political debate and threatening the very functioning of government. But Maine Sen. Margaret Chase Smith stood up to McCarthy and bravely denounced him on the Senate floor. It was the beginning of the end for McCarthy, and the entire world is better and safer for it. As the first woman elected to the Senate without first having been appointed to serve, Margaret Chase Smith paved the way for Susan Collins’ election to that body.

Then there was William Cohen, who in 1974, as a congressman from Maine’s 2nd District and member of the House Judiciary Committee, voted to send articles of impeachment against President Nixon to the House floor. Cohen was one of the first Republicans to openly break with a president who less than two years before had won the biggest landslide in presidential elections. It was a gutsy move for a young freshman congressman.

It was not enough for Bill Cohen to be worried about a corrupt president who was abusing power. Cohen rose to the occasion. His pivotal vote was the beginning of the end for a despotic and dangerous president. In his final days and weeks, Nixon was so out of control that the nuclear codes were taken away from him. That’s how serious it was.

It’s that serious again.

North Korea recently fired a ballistic missile capable of reaching California and maybe even the East Coast. Experts now believe those same missiles may be nuclear armed within a year. We have one year to solve North Korea, and Donald Trump is incapable of solving North Korea.

There’s more.

U.S. military aircraft are flying perilously close to Russian military aircraft in the skies over Syria. This is an extremely dangerous situation not just for the United States and Russia, but for the entire world.

With both North Korea and Syria, what is needed is judgment, prudence and restraint. Trump has none of these things, and he compensates for this with bluster, bravado and aggression.

President Trump has yet to fill many State Department positions that are key to solving these and other dangerous conflicts, and his budget aims to drastically cut the State Department. And his incessant tweets undermine an already incoherent foreign policy.

In both Korea and Syria, aggression risks disaster. North Korea, if attacked by the United States, could decimate Seoul, South Korea, a city of 10 million, and could do so with its existing capabilities, even without nuclear weapons. In addition to very possibly killing millions of innocent civilians, this could greatly destabilize much of the world. With 1.5 million North Koreans under arms, a ground attack could decimate U.S. troops, and China, which borders North Korea, might not stand idly by.

In the face of these two potential disasters, neither the United States nor the world as a whole can afford a U.S. president who encourages and delights in White House chaos and disarray.

In the health care debate and vote, Sen. Collins showed courage and fortitude. It is now time for Collins to follow in the footsteps of Margaret Chase Smith and Bill Cohen and be the first Republican senator to break, in the boldest way she can, with an incompetent, erratic and dangerous president. That way is to leave the Republican Party – that’s how serious and urgent the situation is. Trump must go, and Collins can lead the way.

Circumstances demand bold measures. Bold leadership is needed. It is not enough to be worried, and history will judge harshly those who knew of the danger and did nothing.