President Obama’s decision to normalize relations with Cuba is a decision to recognize reality. For 50 years, the United States has pursued a policy that has failed. The embargo hurt the Cuban people it claimed to help and bolstered the regime that it intended to undermine. The effort to isolate Cuba has been increasingly isolating the United States both in the hemisphere and across the world. And as the president concluded, “I do not believe we can keep doing the same thing for over five decades and expect a different result.” To believe that would be, as Albert Einstein taught us, the very definition of insanity.

The best evidence that this change was long overdue was provided by the hysterical and incoherent reactions of its opponents. Sen. Rand Paul (R-Ky.), a potential presidential contender, embraced the initiative, making an indisputable comment about the embargo: “If the goal is regime change, it sure doesn’t seem to be working.” Sen. Marco Rubio (R-Fla.) replied that Paul “has no idea what he’s talking about.”

Rubio argued that the United States gets nothing in return for normalization: no free elections in Cuba, no free press, no democratic progress of any sort. But while we don’t know what the product of the new opening will be, we do know that the half-century of the embargo hasn’t produced free elections or a free press in Cuba either. By making Cuba David against Goliath, the U.S. embargo provides the regime a rationale for its internal crackdowns while elevating its stature across the hemisphere and the developing world. Normalizing relations with Cuba enables the United States to advocate for individual liberty, without being seen as a bully trying to club a small neighbor into submission.

Why, the president noted, should we continue to isolate Cuba when we normalized relations with communist Vietnam and communist China decades ago? Well, argues a Washington Post editorial that labels the president’s opening a “betrayal,” opposition movements in those countries “barely existed,” while there are dissident movements in Cuba. But the logic of normalizing relations with regimes that eradicate all opposition but not with those that allow some dissent is hard to discern.

Opponents suggest that China and Vietnam prove that “engagement doesn’t automatically promote freedom,” as the Post editorial put it. That is certainly true, as is the fact that 50 years of the Cuba embargo haven’t promoted freedom either. Inescapably, China, a country of more than a billion people on the other side of the world, is likely to be marginally less susceptible to the effects of engagement than a small island of 11 million 90 miles off our coast.

In reality, the failed embargo is long past its due date. Cuba is already in transition from the Fidel Castro era. It has better relations with countries in this hemisphere than the United States does. Investors from Europe, Brazil and China are already doing business there. Cubans have greater rights to travel to the United States than Americans have to travel to Cuba.

What Obama has done is recognize this reality. Opponents don’t seem to realize that history has long since moved on. The Cold War is over; the Soviet Union no more. Cuba is our ally in the drug war; its doctors a blessing in the struggle against Ebola. Cuba’s economy is a shambles, even as its health care and education systems are envied across the hemisphere. Republicans — if Rubio and Sen. Ted Cruz (R-Tex.) are able to overcome the business lobby — may refuse to confirm the president’s nominee as ambassador. They can block the legislation needed to lift the embargo. But with the president’s support, travel can be eased, investment and financial restrictions can be lifted, Cuba can be removed from the list of state sponsors of terrorism, and something closer to normal relations can begin.

Obama’s common-sense initiative also opens the possibility of a sea change in U.S. relations with its neighbors. For more than a century, we have casually and routinely trampled the sovereign rights of our neighbors to the south. We dispatched the Marines to collect debts and defend United Fruit in the early 1900s. During the Cold War, we armed and trained brutal police and military regimes while destabilizing democratically elected governments. And of course, we tried to overthrow Fidel Castro by invasion, embargo and subversion for decades.

In April, Obama will attend the Summit of the Americas in Panama along with other presidents, including Cuba’s Raúl Castro. There, we might listen more and bluster less. The end of the embargo — if it is lifted — may mark the beginning of a new good-neighbor policy, not just toward Cuba but toward other countries in the hemisphere. We would all profit from that.

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