Hamas rockets fell far astray of their intended target — the Israeli Parliament building — on Friday. But as air-raid sirens sounded in Jerusalem for the first time in more than two decades, those errant missiles still delivered another blow to hopes for peace between Israelis and Palestinians.

The spreading bloodshed triggered by Hamas’ relentless rocket attacks should also shatter any illusions about the true nature of an organization that, against all evidence, denies its terrorist nature.

Hamas, which rules the Gaza Strip, has also been firing missiles at Tel Aviv this week. And on Thursday, Hamas rockets killed three Israelis on Kiryat Malakhi in the nation’s southern region.

A day earlier, Israel started responding to those continuing provocations with air strikes on Gaza. As of Friday, the death toll on the Palestinian side in this week’s violence was reported at 23 — 11 of them civilians.

The Obama administration has correctly blamed Hamas for this resumption of armed hostilities.

Israel started calling up thousands of reserve troops on Thursday, sparking speculation of a looming ground incursion into Gaza. As usual, Israel’s critics condemn even the consideration of such a military move. Also as usual, they offer no practical alternatives for a nation where rockets, though notoriously inaccurate, randomly fall, endangering innocent men, women and children.

And those Hamas rockets aren’t Israel’s only serious security problem.

On Friday, Egyptian Prime Minister Hisham Kandil visited the Gaza Strip in a remarkable show of solidarity with Hamas. His trip provided further evidence that Mohamed Morsi, the Muslim Brotherhood leader who was elected Egypt’s president in June, is sharply shifting from the relatively conciliatory stance his nation had long taken toward Israel.

Under the 1978 Camp David Accords, Egypt became the first major Arab nation to recognize Israel.

Yet after that Egyptian prime minister visited Palestinians wounded in those strikes on Friday, he stood beside Hamas Prime Minister Ismail Haniyeh and said: “It isn’t a matter of individuals, not a matter of community. It is a matter of a nation. The Arab nation, the Islamic nation. We are all behind you.”

That certainly appeared to be the case on Friday in Cairo as large numbers of Egyptians protested the Israeli air strikes on Gaza.

Another grim development: The International Atomic Energy Agency reported Friday that Iran is primed to double its output of higher-enriched uranium, an essential material for a nuclear weapon.

Meanwhile, Israel, like Turkey, Jordan and Lebanon, finds itself in the line of fire from Syria’s civil war. Earlier this week, after Syrian mortar shells landed in the Golan Heights, Israeli tanks returned fire and hit a Syrian mobile artillery battery.

And with general turmoil throughout the Mideast on the rise due to the chaotic fallout from the “Arab Spring,” Israel isn’t the only nation in growing peril.

For now, though, Hamas’ escalating rocket attacks represent the most immediate threat to Israel — and raise the risks of an all-out war with the Palestinians.

Israeli Prime Minister Benjamin Netanyahu issued this fair warning Friday: “The Israel Defense Forces will continue to hit Hamas hard and are prepared to broaden the action inside Gaza.”

As Steve Cook, a Mideast specialist at the Council of Foreign Relations, told The Wall Street Journal: “The situation has all the elements and dynamics that could lead us down the road to a place we haven’t been before. It’s a very dangerous situation, and it’s difficult to say what the Israelis should do.”

But it’s clear what the Israelis can’t do: Ignore the ugly realities that are putting their people, their nation and the entire region in intensifying jeopardy.