President Carter glowers at the Russians and talks of "the most serious foreign policy challenge since World War II." But moving around Washington you'd never know the United States and the Soviet Union had moved to the brink.

On the contrary, my impression is that the president first reacted convulsively and in a moralistic fashion to the Soviet invasion of Afghanistan. Thereafter, he reverted to type, put the crisis on hold and prepared to settle.

One bit of evidence comes from the briefing held at the White House for the foreign policy community Wednesday morning. Most of the group favored a strong response to the Soviet invasion and wanted to know what Carter was going to do to follow up the embargo on wheat sales. He had no answer, nor did Secretary of State Cyrus Vance. One participant came away saying: "I suppose when the Russians take Boston we'll cancel the Olympics."

Both the president and the secretary, moreover, spoke in their usual vein. Carter talked of sending the Russians a message. He repeated the usual guff about this country's high standing in the Third World. "He exulted in the morality of his position," one former Cabinet officer said.

Vance said the Russians had made a bad mistake, for which they could be made to pay by the force of international opinion. He sounded, another former Cabinet officer said, as though he would like to get the whole episode behind him, the better to get back to detente.

Zibigniew Brzezinski, the president's national security adviser, was not present. But he too has been playing old games. As usual he has been fighting and losing futile bureaucratic battles for a tougher position. As usual he has been passing word of the battle in order to finger Vance and his supporters as "doves." As usual he has spread it about that a sea change of policy is in the works.

But the sea change does not find expression in the supposed area of confrontation between Washington and Moscow. Instead Pakistan, China, Iran and the Persian Gulf countries are all being given new evidence of American hesitation and self-doubt.

The Pakistanis were first rushed by the president to enter a deal for military assistance. When they asked about terms and scope, Washington promised a reply in 48 hours. The reply turns out to be that the United States cannot supply arms without congressional approval, which will take weeks, and cooperation from the European, allies, which will take longer. So Pakistan, a canary between two cats (Russia and India), finds in the United States a protector that in effect says, "Stand off those cats, and in a few weeks we'll figure out how to support you."

China has brought into the act directly by the visit of Defense Secretary Harold Brown. In keeping with the Vance position, Brown offered Peking almost nothing in the way of arms. In keeping with the Brzezinski position, he talked vaguely of "complementary" action, and announced the sale of a communications station. So the Chinese see the United States talking big and acting small, while the Russians doubtless assume the United States is setting the Mongolian hordes against them.

Four countries close to the Persian Gulf -- Saudi Arabia, Oman, Somalia and Kenya -- have been drawn into negotiations with the United States for air and sea bases to support a larger American military presence in the northwest quadrant of the Indian Ocean. Now Washington says that the bases will only be temporary affairs -- used in a crisis, not at all times. So the recipient countries have to wonder whether the United States is protecting its interest or theirs.

In Iran, after weeks of focusing on the hostages and asserting the principle of putting pressure on Ayatollah Khomeini, the administration now argues that the ayatollah does not control the hostages and that there is no pressure this country can usefully apply. Both arguments seem doubtful in fact. But whether true or not, they are certainly not the right form for going into a confrontation. They suggest, rather, an impulse to back down.

Finally, there is the state of play between Moscow and Washington. After first calling home Ambassador Thomas Watson to protest the invasion of Afghanistan, the United States is now sending him back. Why? Because the Soviet ambassador, Anatoliy Dobrynin, is returning here for talks.

Perhaps the Carter administration is only gathering force for a second effort. Military assistance to foreign countries, higher defense spending, renewal of the draft and a freer hand for the CIA are among the measures this country might want to take in support of the grain embargo. All require time.

But my bet is that Vance and Dobrynin will patch up some kind of a deal. My guess is that the president having lost public support for his handling of the ayatollah and the hostages, retreated forward to confrontation with Russia on Afghanistan, and will now put both Afghanistan and Iran behind him and move forward once again toward detente and arms control.

Whatever the outcome, one point seems clear. The Carter adminstration is not delivering to the American people and to this country's friends, and to the Russians, the one thing all of them most require -- a steady message.