On Fox & Friends this week, I talked with Steve Doocy about Russian dictator Vladimir Putin’s threat that he’s prepared to wage nuclear war.

I told Mr. Doocy America and the civilized world face a real dilemma. We must decide whether we are going to let Mr. Putin do whatever he wants out of fear or stand up to him despite his threats.

As I said on the show, the truth is: If Mr. Putin decided to use nuclear weapons, his country would evaporate. The response from the West would be catastrophic for Russia (and the rest of the world). So, he is potentially running a dangerous bluff.

Suppose we decide to cower instead of standing up. Does that mean Mr. Putin can go ahead and invade the remaining former Soviet satellites? What then? Is it acceptable to let him then take Poland or Germany — because otherwise he might use nuclear weapons?

At what point would Mr. Putin’s nuclear threat be overshadowed by his non-nuclear aggression?

This is a serious problem. Mr. Putin is getting older and more isolated. He may think he’s facing his last chance to rebuild the Russian empire, which has always been his aspiration.

Further, if we allow Mr. Putin’s threats to intimidate us, what message does that send to dictators such as China’s Xi Jinping, North Korea’s Kim Jong Un, or even Iran’s Ayatollah Ali Khamenei?

In some interviews, Mr. Putin has outlined a perfectly reasonable position. He has suggested that Moscow is ready to use nuclear weapons in case of a threat to “the existence of the Russian state, our sovereignty and independence.”

Virtually any nuclear state would draw that line. It implies that the nuclear threat would only come under dire circumstances in which another country or countries have attacked and seriously threatened Russia’s existence.

However, Mr. Putin has also talked about nuclear war as a tool he might use to impose his will on others. He has suggested that Finland and Sweden have made themselves potential targets for nuclear attacks by joining NATO. He has warned that too much Western involvement in Ukraine could lead to the use of nuclear weapons.

In addition to Mr. Putin’s own statements, several of his allies have suggested that nuclear weapons could be used against the West. One ally suggested that Washington, London, and a handful of other capitals could be targeted by Russian nuclear weapons. Others have suggested that Poland or the Baltic states could be targets.

There is a tendency in the American Department of State to respond with great caution and to communicate that the United States must avoid antagonizing Mr. Putin to make sure we don’t drift into nuclear war.

In fact, one argument for slow-walking equipment to help Ukraine fight off the Russian invasion was worry about the possibility of a nuclear reaction by Mr. Putin.

This is exactly the wrong approach to dealing with Mr. Putin and dictators like him. His KGB background has programmed him to believe weakness is an invitation to get tougher and push harder.

The simple fact is that Russia waging a nuclear war, or any war, against America and its NATO allies would be suicidal. A conventional, non-nuclear war would mean a decisive Russian defeat. A nuclear war would mean the end of Russia as a civilization. There would be no Russian cities left standing.

At the conventional level, NATO’s 32 members have an estimated 20,633 military aircraft. Russia has an estimated 4,182 aircraft. This gives a pretty good indication of who would win a traditional war.

At the nuclear level, there are three nuclear powers in NATO — America, Great Britain, and France. Together, they more than match the Russian nuclear arsenal.

Given the catastrophic response from NATO, it’s entirely likely that the Russian military would simply refuse an order from Mr. Putin to start a nuclear war. In fact, it might mean the end of his regime.

America and its allies can and should support Ukraine and take other actions with confidence. In any real showdown, Mr. Putin would lose.

Rather than being intimidated by Mr. Putin’s regular threats, we should ignore them. When necessary, we should openly remind the Russian military and the Russian people how horrible and devastating a real conflict with the West would be.

Mr. Putin will respond to American weakness by taking more risks and becoming even more aggressive. He will respond to American strength by becoming more cautious. Further, his own military will pressure him to avoid any confrontational action that challenges the full power of America and the West.

We must meet threats with strength. Cowardice will only make the world more dangerous.