Suddenly, El Salvador is back in the news - and for the Reagan administration , the news is not good. Guerrilla occupation of the southeastern Salvadorean town of Berlin for a few days this week raises anew questions about the fighting ability of the Salvadorean Army.
That United States-backed army is clearly in disarray, partly as a result of the mid-January mutiny of a disgruntled Army colonel who challenged the Army's top commander and got away with it.
Equally important is fresh evidence, Washington sources say, that leftist guerrillas recently received substantial new weaponry, including sophisticated arms, which has enhanced their fighting capabilities.
El Salvador's political forces are also in disarray and a historic ideological power struggle is again surfacing. Roberto d'Aubuisson, the nation's most outspoken rightist, threatens to resign as president of the Constituent Assembly.
Last week his rightist coalition, which dominated the assembly, collapsed, at least temporarily. D'Aubuisson's powers as assembly president were clipped in the process. Although this could strengthen the moderates in El Salvador, many of them report they have been deluged with death threats, raising the specter of rightist vendettas.
In Washington, anxiety about the situation is deepening, and top Reagan administration officials admit that recent United States policy on El Salvador has been ''confused.''
They admit their goal of creating a moderate, centrist government in the small nation remains elusive.
This week's US and Honduran joint military maneuvers are seen in some quarters as a serious escalation of the US presence in the region. And the wounding of a US Green Beret in El Salvador suggests the range of dangers inherent in any increase in the US role in Central America.
Yet Washington may have to come to an early decision on whether to commit additional US assistance, perhaps even troops, if the military situation is as bad as one State Department source says. That source said the Salvadorean military picture is ''unraveling.''
There is a tendency to put much of the blame for the military's disarray on the mid-January mutiny of Lt. Col. Sigifredo Ochoa Perez, who refused an order transferring him to Uruguay as military attache and demanded instead the resignation of Defense Minister Jose Guillermo Garcia.
Both emerged from the week-long contest having saved some face - Colonel Ochoa being awarded a year's schooling in Washington, General Garcia still in his job. But the incident shattered military morale and seriously disrupted military commands. And some analysts expect General Garcia to step down within a month or so.
This leads some Washington analysts to suggest the need for a new effort to find a peaceful solution to the five-year conflict between the US-backed Salvadorean government and the Cuba-backed guerrillas.
Washington does not want shared power, but it would like to find a formula to end the fighting. If a formula could have been devised two years ago, even a year ago, it might have worked. But there is now some doubt that the guerrillas, flushed with new battlefield victories, would accept anything short of total power, much less shared power.
Jeane Kirkpatrick, the US ambassador to the United Nations, is scheduled to visit Central America shortly - and it is understood she has been asked for policy recommendations.
For the moment, Washington is saying little. But the admission by Assistant Secretary of State for Inter-American Affairs Thomas O. Enders that Salvadoreans perceive US policy as one of ''mixed signals'' - a comment made in testimony before the Senate Foreign Relations Committee this week - was seen by some senators as about the best that could be said for US policy in general.