More than a year before the next presidential election, the effort to win the hearts and minds of the electorate on key national security issues has begun. The politics of defense is evident in a new report by the Republican National Committee (RNC) touting its interpretation of President Reagan's record in this area; in another recent study by a peace group comparing the arms control and military budget records of all major presidential candidates; and in recent polls showing public doubts about United States military activity abroad.
This week a new trade association - Business Executives for National Security - begins raising money to lobby Congress for ''a more businesslike approach to military procurement.''
So far, more than 750 executives (mostly entrepreneurs and independent business managers rather than leaders of large corporations) have signed up, and the list is growing.
Recent disclosures about inflated spare-parts costs and Pentagon contracts awarded without competition have heightened public interest here.
The group includes Republicans as well as Democrats, but spokesman Colburn Aker notes that ''clearly, the type of issues we're taking on are going to be more popular among liberal people.'' The group's emphasis is on weapons procurement and Pentagon management. But it has spoken out against the MX missile and for the nuclear freeze proposal, both highly political issues.
The new Republican document also reflects the political nature of defense issues. Much more space is allocated to debunking the nuclear freeze than to publicizing Reagan administration efforts at Pentagon management reform (a duller subject), which have been earnest and in some cases successful.
''The nuclear freeze is a simplistic, utopian, and irresponsible approach to arms control,'' argues the national GOP leadership. Advocates of the freeze, it says, ''resort to emotional and pseudo-moralistic arguments . . . (and) do not care about verification and Soviet compliance.'' This last point rankles freeze advocates, who say any arms control agreement must be mutual and verifiable.
Opponents of White House defense polices can be just as sharp in their denunciations. Surveying the arms control records of announced and potential presidential candidates, the Council for a Livable World, a Boston-based group of scientists advocating a nuclear freeze, decried Mr. Reagan's ''bellicosity,'' saying, ''the world might not survive four more years of Reagan's unrelenting cold war and massive arms buildup together with no progress in arms control.''
Such rhetoric may already be outdated, at least as it applies to arms control and the freeze. While there have been no breakthroughs at Geneva, and despite the harsh talk in Washington and Moscow, there has been some apparent movement toward compromise. Turnout for pro-freeze activities in major cities around the country during the weekend was quite small, and the nuclear freeze resolution that cleared the House of Representatives earlier this year is given almost no chance of success in the Senate.
On more complex national-security issues such as the Pentagon budget, its economic impact, and deployment of US forces overseas, the process continues to be one of education and assertion.
All of this will require much of voters in sorting out claims and counterclaims.
The GOP report on Reagan's defense record, for example, warns that the USSR spends more than twice as much of its gross national product (GNP) on defense as the US. It does not mention that US GNP is about twice that of the Soviets.
The report echoes Pentagon claims that ''at no time in the Reagan five-year plan are expenditures on strategic forces to exceed 15 percent.'' But the Center for Defense Information, run by former military officers, also adds military construction, Energy Department costs of building nuclear warheads, civil defense, and intelligence activities related to US nuclear capabilities, putting the figure at 22 percent - higher than ever.
The RNC says the newest Soviet intercontinental ballistic missiles (ICBMs) are more accurate than the ''obsolete'' US Minuteman missiles. The International Institute for Strategic Studies in London says the upgraded Minuteman remains the world's most accurate ICBM.