According to Wikipedia, "Fire and Ice" is one of Robert Frost's most popular poems. It was published in December 1920 in Harper's Magazine and in 1923 in his Pulitzer Prize−winning book New Hampshire. It discusses the end of the world, likening the elemental force of fire with the emotion of desire, and ice with hate.

From the website litcharts, “Despite its light and conversational tone, “Fire and Ice” is a bleak poem that highlights human beings’ talent for self-destruction. The poem is a work of eschatology-writing about the end of the world-and poses two possible causes for this end: fire and ice. The speaker uses these natural elements as symbols for desire and hatred, respectively, arguing that both emotions left unchecked have the capacity to destroy civilization itself.” 

The first two lines suggest that the world will end with some catastrophic natural event like the sun exploding or the expanding universe cooling below life sustaining temperatures.  But the focus abruptly changes to human causes and humanity’s ability to create its own disasters.  Fire symbolizes desire which can be a very destructive force and lead to war, violence, greed, anger, and bloodlust.  Ice symbolizes hate, cold and indifference and that the end of the world could be brought about by inaction rather than some singular major event.  Either fire (desire) or ice (indifference) would suffice.  The line “But if it had to perish twice” is confusing.  The end of the world could not occur twice of course.  I interpret Frost’s intention here is to infer that they could happen together, where one leads to the other.  Our indifference to climate change leading to inaction, could bring the world on fire, to a place where it is too hot to sustain life.   We are currently on that tract.  Of course, destruction does not have to refer only to the World.  Unbridled passions and indifference are also destroying our democracy. We see both fire and ice every day in America:  Anger about the discrimination so many of our citizens face occasionally leading to violence in our streets.  Indifference of our President about the more than 200,000 individuals who have lost their lives to the Covid-19 virus, indifference of our President about the many who are suffering financially and limiting the recovery funding to sustain them until our economy recovers.  Indifference of those who will chose not to vote.  Fire represents untempered passion.  Ice represents apathy or repressed or stifled compassion and empathy.  What we need is passion tempered with compassion.  We need reluctant compromise.  We need what seems like an oxymoron.  We need passionate moderation.  We need Joe Biden.  Joe Biden is passionate about his moderation.  Joe Biden is just the right man to bring America back to a nation dedicated to fairness and equally for all.  He will be a unifier, not a divider.  He will lead us to America’s promise. 

Dick Gale

Ice Fire Masked

    Fire and Ice
      by Robert Frost

    Some say the world will end in fire,
    Some say in ice.
    From what I’ve tasted of desire
    I hold with those who favor fire.
    But if it had to perish twice,
    I think I know enough of hate
    To say that for destruction ice
    Is also great
    And would suffice

Fire and Ice