Beginning today, the Cuban policy of requiring citizens to obtain an invitation to visit abroad and permission from domestic authorities to exit the country, is no more. This is a profoundly significant change. Given that Cubans will still need to procure visitor or immigrant visas to most other countries and most without family abroad will have a hard time coming up with the money for the trip, it won’t likely cause a rush for the exits. But the new rules pave the way for a new relationship between country and citizen, and between those who stay and those who have left. The door will now remain open between each, both emotionally and financially.

Though millions of Cubans can now, in principal if not in practical terms, leave the island as they sit fit, there are exceptions for national security and other reasons, and it remains to be seen how Cuban authorities intend to apply them. Last week we learned that Cuban doctors – in whom the Cuban government invests much and expects to return the investment either at home or abroad (on behalf of the Cuban government which contracts them out) – will in fact be free to travel under the new rules. But will critics of the government be free to come and go? The more broadly these new rules extend to Cubans, the more pressure it could put on the United States to change its migration policies toward the island.

If optics matter, we may soon see the administration use its executive authority to further loosen its own restrictions on Americans’ travel to Cuba (to the extent it can). Yes, you might have heard, Americans must seek  permission from the U.S. Department of Treasury in order to be allowed to use our passports to travel to Cuba. The irony of the U.S. “[welcoming] any reforms that allow Cubans to depart from and return to their country freely,’’ as a State Department spokesman put it last week, without doing the same for our own population, will now be painfully obvious.

But it’s not just about optics. It’s about opportunity and the political space to seize it. These Cuban travel reforms provide the Obama administration with an historic opportunity to end our open-door migration policy for Cubans that with every passing year becomes more untenable – especially in a political cycle likely to see action on immigration reform. No other nationality on Earth enjoys the benefits Cubans do, including the right to step foot on U.S. soil illegally and qualify for a green card one year after doing so, and collecting generous adjustment benefits at taxpayer expense to boot.

One would have to go back to John Quincy Adams, who served in the U.S. diplomatic service from the age of 17, to find a predecessor better pedigreed than John Kerry to lead the U.S. State Department. The son of a diplomat, Kerry is a war veteran, senior senator, and the chairman of the Senate Foreign Relations Committee.

Few experiences have had greater influence on Kerry’s foreign policy views than his decades-long relationship with Vietnam, where Kerry served as a swift boat captain during the Vietnam War.

Kerry’s experience in Vietnam, where visceral ideological attitudes prevailed over rational analysis, prompted the future senator to advocate for a more realistic course for U.S. policy. A decorated veteran, John Kerry became a spokesman for veterans against the war. He learned that to promote U.S. values and interests requires awareness of the relative nature of power and the force of nationalism in the post-colonial world.