Free speech on the campus . . .

Going to college in America has traditionally been a lesson in free speech. It is well that national faculty and student organizations have joined in a call to protect this right.

Recent disruptions of campus speeches - and fear of future ones - have clouded the imminent commencement season. Even the most controversial addresses could be safeguarded if all concerned heed the academic group's urgings. It stresses citizens' obligation to respect the freedom of other citizens to speak, ''even those whose ideas we might find abhorrent.'' It adds the obligation of members of the academic community to maintain academic freedom.

Usually the issue of academic freedom arises in resistance to loyalty oaths or other governmental or institutional threats. This week's statement recognizes that this freedom has to be protected from attempts to suppress it by ''members of our own ranks.''

One of the latest campus speech disruptions - directed at Sheikh Yamani, Saudi Arabia's oil minister - was attributed to outside protesters linked to the Middle East. Off-campus elements were also cited when the United States ambassador to the United Nations, Jeane Kirkpatrick, withdrew as Smith College commencement speaker after being informed her security could not be assured during possible protest demonstrations.

Physical security from demonstrators, on or off campus, is a police matter. Security of free speech from those who would shout it down is a matter for everyone in the audience for an address - indeed, for any citizen when any occasion to respect the expression of others' ideas is presented.

The statement by the academic group properly declares that the rights to peaceful protest must also be respected. It notes the difficulty of drawing a line between legitimate dissent and illegitimate disruption.

But learning to draw these lines is part of that very lesson in free speech which is part of going to college in America.