Hamas gets a lot of its trade, munitions, missiles, etc. from Iran and Herzbollah (a Lebanese organization). It really does not need the U.S. to supply it via our trade --- neither does the rest of the Arab world.
A major problem is that the "active" groups in Palestine and elsewhere use "guerilla" tactics that increase the dangers dramatically to the lives of the area's citizenry, e.g., the Hamas hide-out in the midst of a city's populace. Under this cover it makes it hard for a nation like Israel to retaliate, as that cover forces ongoing civilian casualties and then the world points fingers at the nation causing the casualties instead of at the root cause for the fighting that started initially.
I really don't think that Israel had much choice in its retaliation against the Hamas that just happens to be thriving in Palestine. There was a truce that was tossed aside by the Hamas (not the Israelis).
If Israel agreed to a truce now, as most of the world wanted, the Hamas will regenerate its arsenal and eventually will discard the truce again to fire more missiles at southern Israel. It's a cyclical issue.
Who is providing the oversight to force Hamas to exist peacefully without increasing its supply of weapons and missiles?
During the past several years of truce Hamas purchased more weapons, including more up-to-date missiles, from Iran and Herzbollah. Consequently, the Israeli ground forces will flush-out the Herzbollah quicker than longer-distance retaliatory missiles will and also will be slightly less damaging to Palestinian civilians.
Even so, it will take a long time to achieve the objectives set by Israeli leaders, unfortunately at a high cost of civilian lives.
Israel and the Arab world need to settle their differences in a peaceful manner, but neither side seems willing to do so in an ongoing basis. All peaceful efforts resort back to war.