The last time President Obama met with his Latin American and Caribbean counterparts was not a particularly memorable affair.  The 2012 Summit of the Americas in Cartagena, Colombia, was overshadowed by an embarrassing Secret Service scandal that saw members of his advance team soaking in a little bit too much of the historical city's Caribbean nightlife.

Meanwhile, in the absence of any substantive agenda, President Obama spent most of the summit being hectored by his counterparts with the incongruous assertion that undemocratic outlier Cuba must be part of the next meeting of all the popularly elected governments in the Americas.

It was clear the president wasn't pleased with the badgering, complaining that, "Sometimes I feel as if in some of these discussions ... we're caught in a time warp, going back to the 1950s and gunboat diplomacy." 

Fast forward two years: Preparations for the 2015 Summit are well underway and once again Cuba's participation has become the flashpoint.  Governments in Argentina, Venezuela, Bolivia, Ecuador, and Nicaragua have already said they will boycott any summit where Cuba is excluded.  Panama, the host, has announced its intention to formally invite Cuba, with its president saying that the presence of the last military dictatorship in the region was "important."

The State Department has already voiced its opposition, citing the 2001 Summit's agreed-upon "democracy clause," which conditions Summit participation to countries that respect democracy and rule of law.  According to a spokesperson, "So we should not undermine commitments previously made, but should instead encourage -- and this is certainly our effort -- the democratic changes necessary for Cuba to meet the basic qualifications." 

Secretary of State John Kerry privately repeated that message in no uncertain terms to Panamanian Vice President Isabel de Saint Malo when the two met at the beginning of September.

Nevertheless, the drumbeat has started that President Obama must accept the Castro regime's presence at the Summit or else, as one former advisor to President Clinton has said, be "responsible for the collapse of inter-American summitry, 20 years after its initiation by President Clinton."

There is no doubt that U.S.-Cuba policy critics see the president's dilemma as a golden opportunity to mainstream Cuba back into regional polite society despite its uncompromising, repressive rule, thus making it more difficult to justify the U.S. policy of isolating the Castro regime politically and economically.  The administration will therefore be coming under enormous pressure to accept the "inevitable" and attend the Summit with Cuba. 

These critics understand the power that symbolism plays in international affairs.  The presence of a U.S. President at any event -- international or otherwise -- is never routine, or ever lacking of import and consequence.  Thus, in their construction, President Obama's attendance at a Summit with Cuba will signal a U.S. surrender of fifty years of its embargo-centric policy.  On the other hand, the symbolic importance of standing up for the region's hard-won democratic gains over the past quarter-century by making a point about the incongruity of Cuba's presence in this age of regional democracy will be a dagger in their heart.

It's worth noting that several of the governments insisting on Cuba's presence are those guilty of their own back-sliding on respect for democratic institutions over the last several years, including Venezuela, Bolivia, and Ecuador.  Why wouldn't they want the Castro regime present in regional fora, so as to lower the bar for everyone on adhering to democratic principles?

But this isn't just to argue that President Obama should just stiff his counterparts and appoint a lesser State Department official to attend in his stead if other Latin American governments insist on Cuba's presence.  The president should seize the opportunity to be proactive and make a statement that what distinguishes the Americas is that it is a community of democracies and that commitments to democratic governance are enduring and meaningful to ensure it will always be that way.  He should challenge others to argue why the Castros' military dictatorship is deserving of any special consideration or compromise for their flaunting of democratic norms over the past five decades. 

If, in the end, the president opts not to attend the Summit due to the Castro regime's presence, meaning that the U.S. "isolates" itself from the Summit process, then so be it.  Principle is more important that popularity.  The sun will rise the next day and the struggle for democracy in Cuba will continue.  And if Latin American governments choose to condition their relationships with Washington on U.S. relations with Cuba, that is their choice to make -- and to live with.

YAMIL LAGE/AFP/Getty Images