Last week, the Senate approved the nomination of career officer Roberta Jacobson to be the next U.S. ambassador to Mexico. The vote came after Sen. Marco Rubio, R-Fla., lifted his hold in exchange for an extension of sanctions against human rights violators in Venezuela.

It was a good deal. We will have a senior representative in Mexico as that important bilateral relationship is coming under tremendous pressure due to the ravings of presidential candidate Donald Trump, while the United States will continue to maintain some leverage over events in Venezuela as that country descends into turmoil.

In fact, it is with the latter situation in mind that the Senate would do well to vote on another nominee caught in the thicket of the nomination process: Mari Carmen Aponte, as U.S. Representative to the Organization of American States (OAS).

I admit to being skeptical of Ambassador Aponte when she was nominated to be U.S. ambassador to El Salvador. My doubts were based on issues raised during the Senate's consideration of her nomination to another post by President Bill Clinton nearly two decades ago. Those matters are in the distant past, while her recent able service in San Salvador has earned her high marks. Based on conversations with Salvadorans whose opinions I trust, Aponte effectively defended U.S. interests before the leftist government there. In short, her toughness and energy persuade me to urge the Senate to afford her a confirmation hearing and vote for the OAS position at this crucial time.

Indeed, one could be forgiven for dismissing the relevance of the OAS following the disastrous tenure of the recently departed Chilean Secretary General José Miguel Insulza (2005-2015), who sought to use his position as a platform to run for the Chilean presidency and, when that didn't pan out, had neither the inclination nor the wits to turn the organization into a regional player.

But things are changing under the new Secretary General Luis Almagro of Uruguay. As the Washington Post's Jackson Diehl put it, "Almagro's simple strategy has been to do what no other senior figure in the Western Hemisphere -- Americans included -- has done in the past two decades: publicly call out and denounce violations of human rights and democratic practice whenever and wherever they occur in the hemisphere, in detail and without regard for diplomatic nicety."

The hitch in this effort is that the United States has no ambassador at the OAS to help sustain this effort, at a time when deteriorating conditions in Venezuela are on the verge of sparking a regional crisis and active diplomacy is sorely needed in efforts to ward it off.

The OAS remains the last, best hope for an intervention in Venezuela. In fact, under the Inter-American Democratic Charter, the OAS has the regionally accepted authority to intervene in the event of an "unconstitutional alteration of the constitutional regime that seriously impairs the democratic order in a member state." The sustained campaign of the Nicolas Maduro government to systematically undermine the powers of the opposition-controlled National Assembly certainly qualifies as that.

But it will take quiet, determined U.S. leadership to rally the region and press the OAS to address the Venezuelan issue urgently and, under the Charter, develop an emergency political and humanitarian initiative to head off more violence, and a collapse that would bring instability to the region and further the deprivation of Venezuelans. That cannot happen without an effective U.S. ambassador in place. It's time for principle to take precedence over politics.