In his General Assembly speech on Sept. 24, 2013, Mr. Rouhani pledged “to open a new horizon in which peace will prevail over war, tolerance over violence, progress over bloodletting, justice over discrimination, prosperity over poverty and freedom over despotism.” One year on, how have these promises fared?

Peace over war? Hamas in Gaza rained hundreds of Iranian-supplied missiles on Israel in a seven-week campaign to terrorize civilians. In Syria, Iran’s infusion of cash, weapons, military advisers and its Hezbollah-backed militias have kept Bashar Assad in power and over the past year produced tens of thousands more casualties.

Tolerance over violence? At Iran’s behest, Nouri al-Maliki’s Shiite-led government in Iraq systematically arrested, tortured and murdered members of that country’s Sunni minority, not to mention the deadly attacks on Iranian dissidents, which killed five dozen, 52 of them execution-style. Iraq’s armed forces and intelligence services were systematically purged of Sunnis. These deliberately repressive policies paved the way for the stunning political and military conquests in Iraq by Islamic State terrorists.

Progress over bloodletting? The one arguable bright spot in Iran’s relations with the civilized world has been its willingness to negotiate over its nuclear program. Yet with a November deadline looming, there are few if any signs of progress toward an agreement. Iran has kept enriching uranium 235 to reactor grade levels, thus accomplishing nearly 70% of the enrichment necessary to reach weapons-grade levels. Iran’s weaponization research and ballistic-missile development are not limited in any respect and proceed apace.

In violation of its obligations, Iran has blocked or severely limited access by inspectors of the International Atomic Energy Agency to key nuclear facilities. In its latest report, on Sept. 5, the IAEA wrote that it is unable “to conclude that all nuclear material in Iran is in peaceful activities.”

More troubling are statements by Iran’s leadership. On July 7 Supreme Leader Ali Khamenei said that Iran needs to “significantly increase” its number of centrifuges. In April this year he told a group of Iranian scientists: “None of the country’s nuclear achievements can be stopped.”

Prosperity over poverty? Mr. Rouhani has leveraged the nuclear negotiations for significant financial gain. The easing of U.S. and European Union sanctions has provided Iran access to more than $6 billion in frozen assets and tens of millions more through oil sales. The Iranian people have seen little from the sanctions relief, while the regime in Tehran continues to bankroll its terrorist proxies and military-industrial complex.

Freedom over despotism? Since taking office, Mr. Rouhani’s government has executed 1,000 Iranians, according to human-rights monitors inside Iran and ranks first in the world in per capita executions, which included hundreds of women, youths, ethnic minorities and dissidents. The State Department documented Iran’s dismal record of respect for human rights in its 2014 report on human-rights practices.

The list of Iranian excesses is sickening, “including judicially sanctioned amputation and flogging; politically motivated violence and repression, such as beatings and rape; harsh and life-threatening conditions in detention and prison facilities, with instances of deaths in custody.”

The legal and political system is a travesty, including “arbitrary arrest and lengthy pretrial detention; continued impunity of security forces; denial of fair public trials; the lack of an independent judiciary; political prisoners and detainees; arbitrary interference with privacy, family, home, and correspondence; severe restrictions on freedoms of speech (including via the Internet) and press; censorship and media content restrictions; severe restrictions on the freedoms of assembly, association, and religion; legal and societal discrimination and violence against women, children, ethnic and religious minorities; incitement to anti-Semitism; and trafficking in persons.”

Delegates to the U.N. General Assembly might want to keep Mr. Rouhani’s dismal record in mind when he mounts the podium on Thursday, no doubt offering fresh promises of Iran’s peaceful and just intentions. It is time that the international community held his government to account and insisted that words be matched by deeds. Absent that, we must be clear-eyed and under no illusion about the regime with which we are dealing.

Mr. Ereli was U.S. ambassador to Bahrain (2007-11).