According to A promotion for female soldiers, the Israeli army — a no-nonsense organization — has had some success with female infantry:
Hoping to relieve units stretched thin by the Palestinian uprising, the army created predominantly female companies three years ago to patrol the border for drug smugglers and the rare terrorist infiltrator. Only men served on the more dangerous Lebanese border and in the Palestinian territories.
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Israeli army doctors recommended in October that women be barred from service in combat units on the basis of medical studies showing that they are less able than men to lift heavy objects and carry out sustained, strenuous activities.The doctors, however, said there was no objection to women serving in light infantry units along peacetime borders, as the Carcal company does, or as radar operators in intelligence units, where they have proved themselves on numerous occasions.
The United States bans women from ground combat units, which include artillery, infantry and armor. They may, however, serve on combat ships and aircraft. And they serve as military police, a job that in Iraq puts them close to counterinsurgency operations.