Lifting of some US sanctions has not solved Poland's problems.

''A small step in the right direction.'' That was what the United States called the Polish amnesty. And the Poles have just said the same thing about America's initial easing of sanctions.

But after both moves, the question remains to what extent, and how soon, these actions might actually prove to be a step in the ''right direction'' for Poland itself.

Political confusion continues to pervade the country. There is uncertainty about whether Poles can reach the kind of social agreement among themselves that would make any real solution of their crisis possible.

''Social agreement'' was the hoped-for ideal behind the strike settlements worked out by the government and the now-banned trade union Solidarity in that fateful August four years ago. Within a few months, however, the elusiveness of such agreement became apparent as each side sought to stretch the Gdansk and other accords to their own advantage.

There is something reminiscent of that period now, a fortnight after the amnesty, with the more extreme of the recently released union militants talking as though nothing had changed and saying that Solidarity's legal status might shortly be reinstated.

While the Polish authorities said that thoughts of any return to the past were illusory, they did not exclude, over the long term, a partial development of the popular participation and plurality in affairs for which Solidarity initially stood.

But the Polish government's first response to US reduction of sanctions was grudging, reflecting the continuing presence of a hard-line element in the Polish leadership.

The sanctions that were lifted - those against scientific links with Warsaw and landings in the US by the Polish airline LOT - were certainly minor.

The major US sanctions are still in force: the withholding of most favored nation trading status, the freeze on new US credit, and Washington's opposition to Polish re-entry into the International Monetary Fund.

Polish recovery will not be brought about by LOT's freedom to fly planes into the US again, nor by academic contact. What Poland wants is practical access to, and credit with which to fund purchases of, American technology.

Western sanctions were devised to secure the release of political prisoners, a return to dialogue between rulers and ruled (including the Roman Catholic Church), and ''free'' trade unions. This is how things stand on these issues:

* Political prisoners are now being rapidly released. (Poland's most prominent dissident intellectual, Jacek Kuron, was released from prison Thursday , his relatives told Reuters. Mr. Kuron, a senior adviser to Solidarity and a founder-member of the dissident group KOR (Workers' Defense Committee), had been held since December 1981.)

But the future of two prisonsers who face charges of treason is unclear. Solidarity leader Lech Walesa has appealed for their release.

* Church-state dialogue between Polish leader Gen. Wojciech Jaruzelski and Polish primate Jozef Cardinal Glemp has yet to be open and direct.

But, though it has been little publicized, the government has finally agreed that the church alone should administer a Western church-sponsored agricultural fund designed to assist Poland's vast army of small private farmers. This will be done through a church council with the necessary experts and appropriate consulation with, but not official control by, the authorities.

* As for trade unions, it was no surprise that talk of a ''new campaign'' by some of the first freed Solidarity organizers drew immediate official rejection.

But the latest reports from Warsaw are that moderate union voices are also being heard, that the extreme militancy of the old order is not reflective of rank-and-file feeling, nor of public opinion at large.

These moderates say that the most realistic and constructive course is for former Solidarity members to join the new unions and so be better placed to ensure official respect of their legally prescribed ''independence.'' They urge Solidarity's old members to seek election to self-management committees now installed in almost every enterprise, for which General Jaruzelski has frequently affirmed strong commitment.

''Sooner or later we shall have to join the unions,'' says a Solidarity source from Warsaw. ''It is a question of the realities of the situation. They haven't changed.''

By ''realities,'' he means that Jaruzelski has gone just about as far as he can in meeting the internal and external pressures upon him. He still has to reckon with political ''no go'' areas, imposed both by the anti-reform faction in his own party committee and by Soviet opposition to even moderate reform.

''To talk of a return to plural unions - particularly in the Russians' present mood - is pointless,'' this source said. ''Even if he gave it a thought - and he wouldn't - Jaruzelski could never get it past Moscow. It is a reality the Americans, as we ourselves, must recognize.''

Jaruzelski will face another such ''reality'' if and when the US lifts its blockade to Poland's accession to the International Monetary Fund, which could provide Poland with hard currency.

The first half of this year has seen a steady and above-plan 4.8 percent higher growth of nationalized industrial output compared with 1983. Coal, steel, and the light industries are doing well.

But incomes still rise faster than production. Acute hardships remain, though in Polish terms there has been a marginal improvement of living standards.

IMF membership could therefore be a mixed blesing. It could provide the best prop for government recovery programming. But it would also entail much stricter income and pricing policies and a new belt-tightening.

Such moves, coming on top of the present austerity, could easily rekindle the old discontent.

Poland must still agonize over a closed circle of interlocked needs - debts, credit, credibility, and so on. Only a decision now by the West to remove their remaining sanctions against Poland could be effective in helping to break that circle.

And only that, many of the most experienced Poland-watchers believe, would ensure that the amnesty, the first step in national conciliation, is kept on course.