A star glows each night from the slopes of the Franklin Mountain range overlooking this border city. For almost a year now it has been a daily reminder of the hostages in Iran, retained since the Christmas season at the wish of local officials. People you meet talk voluntarily about the star and its symbolic meaning; they have not been able to get Iran out of their minds. It remains a troubling, underlying concern among voters in this presidential election year.

The subject of the hostages cannot be separated from another deep concern: war. "People are very fearful of war," a community leader said. "I think whoever succeeds in making his opponent look warlike will be successful in the campaign."

That was heard in the first interview conducted here. It came only two days before flames began rising in the Persian Gulf, before President Carter linked Ronald Reagan with warmongering, and before Reagan in turn laid the blame for the latest Mideast conflagration on Carter.

"What is happening in Iraq and Iran is the consequence of policies this administration has followed during the last 3 1/2 years -- a vacillating foreign policy and a weakened defense capability are largely to blame," Reagan said in a campaign appearance here in El Paso.

Once again, whether justified or not, and whether or not the politicians are engaging in demagoguery over the most emotional of all issues, the spectre of war hangs over an American presidential campaign.

The 1980 presidential election was supposed to be dominated by domestic issues, and for good reason. Month after month brought more doleful news -- the highest interest rates in 150 years, the steepest inflation in a lifetime, the continued slide of the dollar, the sharp rise in unemployment, the decline in productivity, the inability of our industrial complex to compete effectively in world markets. All in all, the worst economic picture since the Depression.

These domestic problems obviously affect people when they weigh their presidential choices. But now, as has been the case for almost 12 months of campaigning, international questions are overshadowing them.

At this point, they are working toward Carter's advantage, though not because people believe Carter has been successful in handling them. He gets universally poor marks for his supervision of American interests overseas. And Reagan's greatest opportunity lies in capitalizing on the overwhelming sense that America's position in the world has eroded seriously. This raises doubts among people everywhere about the future, and creates the climate for political change that exists in the country today.

Obviously these views are contradictory; they pose the sharpest paradox -- and perhaps most significant political fact -- of the election. This complex of emotions that appears likely to determine the presidential winner five weeks from now is best exemplified in the feelings about Iran and the hostages.

In the history of this presidential year, Iran represents the main text. It was the taking of the hostages, exactly one year before Election Day, that transformed Carter from almost certain loser to invincible candidate during the long primary season then about to begin.

Through television, the sight of those chanting Iranian mobs burning American flags and shouting "Death to Carter" gave him something he had not been able to achieve before. Carter became the personification of the nation, the visible symbol behind which Americans rallied in time of trouble. As the Iranian crisis continued, Carter's popularity soared. The vast majority of people approved his handling of the situation. That reversal of political fortunes was the most dramatic in the history of American public opinion polling.

After the unsuccessful rescue attempt last spring, it seemed the Iranian issue had disappeared from public consciousness. It's true the press stopped highlighting it so intensively, and people tended to drop the subject from their conversations. But you cannot travel the country today without being struck by how deeply Iran remains lodged in people's memories. In any long conversation, Iran always comes up. lIt continues to be deeply troubling, a frustrating symbol of American impotence, of how we no longer seem able to solve major problems. "I haven't put it out of my mind," one person here has said. "I don't think we should. Maybe it's not the most important thing -- but come to think of it, it is."

And now it's hard to find anyone who gives Carter credit for Iran. He's faulted for not doing enough to solve the situation, or for bungling it. That it would seem, should spell political trouble for him. So it would if it were the only factor in people's minds, but overriding it lies a deeper concern -- the threat of war.

Lucy Acosta, a Mexican-American community leader, expressed the complicated feelings of many: "I'm still very incensed over the fact that we have not been able to free our hostages. But I also realize that if we went in there and showed our might we might be involved in World War III. It could happen. It's pretty sad we cannot free our people, and I want to punish them. I'm very determined that we show them we mean business. The United States just has to show some kind of backbone. I don't know how we're going to do it. If I did know, I'd be up there in Washington making the decisions."

What appears to be working politically now, as the TV screens again bring violence into our living rooms, is a reassertion of a familiar pattern. In times of danger, Americans look toward their president for assurance. They also are wary in such times about presidential change amid a period of crisis. For all his perceived failures, Carter still gets credit for having gained hard-won experience during difficult hours. The fact that he's the one who has been "up there in Washington making the decisions" gives him an advantage as fear of war increases.