The latest flare-up of the chronic debate over arms sales to Saudi Arabia and Israel comes at a time when some basic truths about the Middle East are especially clear.

If anyone doubted that both Israel and Saudi Arabia face military threats, the present crisis in the Persian Gulf dispels that uncertainty.Israel has repeatedly had to fight to defend its existence. It is surrounded by openly hostile neighbors, with one exception. Egypt alone has been willing to sign a peace treaty.

And the threat to Saudi Arabia is now tangible. The expansionist ambitions of Iraqi dictator Saddam Hussein have already propelled him to invade two of his neighbors, Iran in 1980 and Kuwait in August. Next in line is Saudi Arabia.

The American interest in preventing this irresponsible militarist from controlling the gulf oilfields - on which much of the world depends for energy - coincides with Saudi Arabia's interest in self-defense.

Israel has been lying low in this crisis - as all agree it should, lest Saddam exploit anti-Zionist feeling to fracture the unusual Arab-American alliance against Arab Iraq.

But Israel is very much part of the present equation. Its proven military prowess is an unstated but valuable asset to Operation Desert Shield.

Recent events only underscore Israel's importance as a longtime strategic ally of the United States, receiving $1.8 billion a year in military aid.

Appropriately, the Bush administration remains committed to helping Israel maintain its qualitative military superiority in the region.

But now more than ever it is also desirable that the Saudis have the capability to defend their borders.

The $7.5 billion in weapons sales the administration has proposed is huge but not necessarily unreasonable considering the billions of its own the United States is spending in Saudi Arabia's defense.

No one knows what kind of Middle East will emerge once the dust settles from Saddam's invasion of Kuwait. Ideally, it would be a region no longer prone to the use of force. Very likely, however, it will remain a place where Israel and Saudi Arabia both must be strong to be safe.