The Senate is about to begin consideration of its version of the 1987 trade bill. On the whole, we believe the bill contains many positive features. However, it also contains one glaring special-interest provision that cannot be ignored. In an effort to protect the domestic oil industry, the Finance Committee bill includes a provision that would expand presidential powers to a degree that we believe most Americans would consider unjustifiable and unwise. Under the amendment, if oil imports exceeded 50 percent of domestic consumption or were to exceed 50 percent of demand within a three-year period, the president could unilaterally:

Impose tariffs and quotas on oil and gas.

Decree changes in tax law, regardless of budgetary impact.

Decontrol natural gas prices.

Mandate energy rationing or conservation measures.

Each of these measures would necessarily result in price increases to the consumer.

Proponents of this plan claim that it would not really expand presidential authority. It is true that existing trade law gives the president broad powers to "adjust" imports. The president can only exercise these powers in an emergency -- that is, when the imports threaten national security. However, it appears that the measures the president could take under this proposal greatly exceed those measures he could take under present law. More important, the new provision demands that the president use what are now emergency powers in situations that may be neither critical nor threatening.

At the heart of the amendment is the notion that when oil imports exceed or are projected to exceed an arbitrary level (in this case 50 percent) of U.S. demand, national security is imperiled. There is no analytical basis for this 50 percent threshold. An energy emergency could occur at a lower level of imports. For example, oil imports made up 35 percent of U.S. demand in 1973, when the OPEC embargo was first imposed. Today, they are at roughly the same levels with no ill effects in the nation as a whole. Alternatively, imports could be significantly higher than 50 percent without putting national security in jeopardy.

America's vulnerability to oil-supply disruptions does not depend on the volume of oil we import. As long as the United States consumes any oil, we will be affected by oil-supply disruptions no matter where they occur.

In the short run, the best protection against a supply disruption is our Strategic Petroleum Reserve. The SPR is the only quick way for the federal government to compensate for a sudden cutback in oil supply. Expanded oil depletion allowances, or tax holidays for certain oil producers, won't create oil in an emergency.

The oil security amendment has a disturbing "Fortress America" quality to it. First, the amendment fails to distinguish among sources of foreign oil. Clearly, oil from the Persian Gulf is less secure than oil from our neighbors in Mexico, Canada and Venezuela. Moreover, many of these countries need to sell us their oil to pay the money they owe American creditors.

Responsible energy policies are crucial to the nation, but these policies cannot deny the reality we face. Oil production in the lower 48 states peaked in the early 1970s. Production is unlikely to reach earlier levels, regardless of tax subsidies or higher prices. Alaska oil production probably has likewise peaked. Barring some fantastic energy breakthrough, such as fusion power, cheap supeconductors, a recession or Draconian conservation measures, oil imports will eventually exceed 50 percent. The 50 percent threshold would then trigger quotas, rationing and price controls, and we would be back to the same discredited policies that brought us the long gas lines and protracted recession of the 1970s.

There is an even darker possibility. A president could easily bypass Congress on some of the most sensitive national policy issues. By manipulating the assumptions on which the oil-import projections are based, the president could decontrol natural gas prices, allocate oil supplies from one region of the country to another, or suddenly lease environmentally sensitive areas off the California or Alaska coasts for oil and gas development.

Congress has a constitutional responsibility to involve itself in energy policy decisions whenever possible. This provision would abrogate that responsibility, turning over control of energy policy to the president. No one would argue that the president should not possess emergency powers flexible enough to allow him to deal with a range of true national crises. However, if we grant these powers to the president in unthreatening circumstances, Congress places its traditional powers and responsibilities in jeopardy.Bob Packwood is a Republican senator from Oregon. Bill Bradley is a Democratic senator from New Jersey.