Is there any element of American foreign policy that has failed more abjectly than our embargo of Cuba?

When I hear hawks denouncing President Obama for resolving to establish diplomatic relations with Cuba and ease the embargo, I don’t understand the logic. Is their argument that our policy didn’t work for the first half-century but maybe will work after 100 years?

We probably helped keep the Castro regime in power by giving it a scapegoat for its economic and political failures. Look around the world, and the hard-line antique regimes that have survived . Cuba and North Korea . are those that have been isolated and sanctioned. Why do we think that isolating a regime is punishing it, rather than protecting it?

Few initiatives failed more catastrophically than the American-backed Bay of Pigs invasion of Cuba in 1961. Yet while an armed invasion failed, I bet that we would have done better if we had permitted invasions of tourists, traders and investors.

American tourists in Havana are already asking plaintively why Wi-Fi is so scarce . or why the toilet paper is so rough. We need hordes of them, giggling at ancient cars held together with duct tape, or comparing salaries with Cubans.

Sometimes the power of weaponry fades next to the power of mockery.

When I was a law student in the early 1980s, I financed a visit to the Soviet Union by smuggling in bluejeans and Walkmans and selling them on the black market. My Russian customers regarded my goods with reverence, and me with jealousy. The craving for cool consumer goods was perhaps as much a factor in the toppling of the Soviet empire as the yearning for voting rights.

Our economic embargo hurt ordinary Cubans, reducing their living standards, without damaging Cuban elites. The embargo kept alive the flames of leftism in Latin America, creating a rallying cry for anti-imperialists.

The United States, over the years, considered bizarre assassination plots against Fidel Castro, like an exploding seashell. There were also proposals to humiliate him by drugging him with a hallucinogen, or using a depilatory to make his beard fall out. Our tax dollars at work.

Senator Robert Menendez, a Cuban-American Democrat, objects that “President Obama’s actions have vindicated the brutal behavior of the Cuban government.”

Likewise, Senator Marco Rubio, a Cuban-American Republican, denounces the approach as “based on an illusion, on a lie, the lie and the illusion that more commerce and access to money and goods will translate to political freedom for the Cuban people.”

The critics are absolutely right that the Cuban regime is both oppressive and economically incompetent. But wishing unpleasant governments away doesn’t have a great track record.

My views are shaped by having lived in China for a time in the 1980s when the country was opening up to the West. Waves of foreign visitors were deeply unsettling to Chinese who believed in the system.

In 1983, a British friend of mine returned to his hotel to find his contact lenses missing from their case. He asked the hotel staff, and one cleaner explained proudly that he had washed out the contact lens case in the sink.

An uproar followed. Soon all the Chinese staff in that hotel learned, with wild surmise, that Westerners had access to tiny, invisible glasses that they could put on and take off. They absorbed this with astonishment and envy.

Senator Rubio is right that encounters with new technology and wealth are not immediately lethal to authoritarianism. After all, the Chinese Communist Party is still solidly in place, and even imprisoning the great Nobel Peace Prize winner Liu Xiaobo.

Yet these encounters are if not lethal, at least corrosive. China has become less monolithic because of its interactions with the world. There’s no political pluralism in China, but there is economic and cultural pluralism. Maoist days are forever gone.

Likewise, I’m struck how often North Korean defectors have told me that they had a change of heart simply by visiting China or Russia and seeing themselves patronized as backward.

During the North Korean famine in the 1990s, the government there tried to console the starving population with television programs about the dangers of overeating, including a documentary about a man who ate too much rice and exploded. At the time, North Koreans would stare at the rare visiting foreigner, especially anyone a bit rotund, with a transparent range of emotions: jealousy, awe, and perhaps a bit of wariness in case of detonation.

So bravo for the new Cuba policy. Sending in gunmen to liberate the Bay of Pigs failed. Maybe we’ll do better with swarms of diplomats, tourists and investors. Preferably plump.