Your response is as simplistic as those who say we need to stay entrenched along the Jordan river in order to maintain secure borders. The real issue is what do you mean by secure. Could Israel repel an invasion launched from the '67 border (which to remind you, is just a few kilometers from the sea at its narrowest)? It depends who's invading, if it's a large army like, say Iran's or Iraq's under Hussein, the answer is probably no - so clearly there need to be limits on foreign armies in Palestine and the size of the Palestinian forces. It's also clear that the '67 lines will expose all of central Israel to rocket, mortar and artillery fire (just like the Israeli communities near the border of Gaza), so anyone who supports establishing the borders along the green line (myself included) needs to be aware of these facts and be prepared to support security measures Israel needs in order to permit a pull back.
Law expanding definition of terrorist activity passes first Knesset reading (Haaretz)
from the article: Setting Palestine's borders