Militants have done so much of the dreaming for Gaza’s Palestinians for so long that others seem almost to have lost the habit.Gazans are now tentatively contemplating an unfamiliar possibility—new freedom. Most have what may seem modest notions of what to do with it.‘‘To go upstairs,’’ said Muhammad Bashir, age 12, when asked what he dreamed of after the withdrawal. His home is near an Israeli military base guarding the settlement of Kfar Darom. At the start of the last Palestinian uprising almost five years ago, the Israeli army took over the upper two floors.The army’s constraints are a major part of life here. Haya Bashir, also 12, dreams of once again being able to play hide-and-seek outside. ‘‘I can only play inside,’’ she said.Some Palestinians doubt the Israelis will really go.Others wonder how soon and how far Israel will relax its control of Gaza’s boundaries, airspace and coastline.To the west, the Mediterranean horizon looks limitless, an open invitation to dreamers. But an Israeli naval blockade keeps Gaza’s fishermen’s ambitions in check.‘‘To fish wherever we want,’’ said Nasser Bakr, a 40-year-old fisherman, when asked his own hopes for life after the Israelis leave Gaza. ‘‘Fish are not stuck in one place. —NYT