Now 90, and approaching the 68th anniversary of his arrival in Israel, Arens says he never fails to appreciate the military, scientific, economic and social accomplishments the country has made since the pre-state era.

"If you look at the years of Israel's independence, I think it's all good," Arens said.

"Of course, you've had ups and downs, but the curve is all good. I get asked sometimes 'What would [Theodor] Herzl think if he looked at Israel today?'

"And I quote my wife: Herzl would say 'wow!' Herzl couldn't have imagined that this is what the Jewish state would eventually become - strong economically, strong militarily, an advanced country with great things happening all the time, defeating all its enemies - how could he imagine that?"

Given the arc of Arens' life, his sense of optimism was far from a given.

Born in Kaunus, Lithuania, in 1925, he spent his teenage years in New York - the family escaped the Holocaust by emigrating to America on September 7, 1939, just a week after the outbreak of the Second World War.

There, he joined Betar, the youth group associated with Vladimir (Ze'ev) Jabotinsky's Revisionist movement, eventually becoming the head of the group and a member of the Diaspora branch of the underground Irgun Zvai Leumi, headed, from 1943 to 1948, by Menachem Begin.

He arrived in Israel in the summer of 1948 towards the end of the War of Independence.

Upon arrival, Arens' association with the Revisionist movement made him persona non grata to the Labour Zionist establishment.

"People associated with Betar were definitely considered 'outside the camp'," he recalled.

"People had trouble getting jobs. I was probably the only MIT-educated engineer in Israel at the time, but I couldn't get a job suitable for my qualifications.

"I interviewed for a job at Israel Military Industries - they thought I was qualified, but when it came time for my security clearance, I wasn't cleared.

"So my wife and I volunteered to help establish a border settlement, Mevo'ot Beitar, later renamed Mevo Betar, located right on the armistice line in the hills south of Jerusalem, adjacent to Wadi Fukin and Husan.

"After a year there, I went back to America, did my master's degree at CalTech and, by the time we returned to Israel, the Technion was looking for a specialist in propulsion.

"Technion president Yaakov Dori was a former chief of staff, but he didn't care about party affiliations if he felt you could do the job and he was happy to hire me."

Five decades later, Arens speaks about the enmity between the Labour and Revisionist Zionist camps with an ongoing sense of shock, perhaps also sadness, but no trace of anger.

He talks openly about the frustrations of being a Revisionist during the pre-state period and the early years of Israeli independence - accusations that Revisionists killed Jewish Agency head Chaim Arlosoroff in 1933; David Ben-Gurion's condemnation of Revisionist philosopher Jabotinsky as 'Vladimir Hitler'; and later Ben-Gurion's refusal to refer to Begin to illustrate the history of that era.

Arens's 2011 book Flags Over the Warsaw Ghetto: The Untold Story of the Warsaw Ghetto Uprising tells the story of Revisionist fighters, led by Pawel Frenkel, who were active in the 1943 revolt against the Nazis.

Arens says Frenkel's name barely appears in "official" histories of the ghetto uprising, which focus instead on Mordechai Anielewicz, leader of the Zydowska Organizacja Bojowa (Jewish Combat Organisation).

"It's obviously an ideological rift that runs very deep - even in those desperate circumstances, Labour Zionists insisted that Jabotinksy's people were fascists and they refused to collaborate with them in any way," he said.

"To this day, they refuse to even acknowledge the heroic role that Revisionists played in the ghetto.

"It is a classic example of appropriation of history in order to glorify the Labour Zionist movement and also to avoid showing the Revisionists in any positive light at all."

Perhaps, as a result, Arens feels a particular sting about accusations that Israel has started to display 'fascist' tendencies. He acknowledges that while every country in the world could stand improvement in some areas, the building blocks of Israel's democracy, particularly freedom of speech and voting rights, are as solid as any country in the world.

At 90, he is long retired from the political stage and his years as defence minister are long past, but the clarity of his thought has not dimmed. Neither have his views.

He remains deeply committed to Revisionist Zionism, and is regarded as a confidant and elder statesman to current Likud MKs, many of whom he says consult with him regularly about the issues facing the country today.

If there is any moment in the discussion when Arens turns coy, it is at the mention of Prime Minister Benjamin Netanyahu, whom Arens nurtured as a prodigy when the latter served as ambassador to America.

Predictably, Arens is loathe to discuss the details of Netanyahu's domestic and foreign policies, other than to praise the prime minister's "capability" and express admiration that Netanyahu has survived so long at the helm.

As for the notion that Netanyahu has abandoned Israel's diplomacy by failing to appoint a full-time foreign minister, Arens feels that Netanyahu's ability to impress, combined with the "excellent" director general of the Foreign Ministry, Dore Gold, is sufficient to identify and work effectively toward foreign policy objectives around the world.

"Sure, it might be better if someone took it on as a full-time job, but considering Netanyahu's ability to impress people, the fact that Netanyahu is the foreign minister [is a good thing]," Arens said.

"Look at the developing Israeli ties as the result of the prime minister's trip to Africa, at the establishment of diplomatic ties to certain Muslim-majority countries.

"So, it's not really that Israel doesn't have a foreign minister. Our ambassadors are working, and it looks like they are making progress."

In the defence arena, too, Arens says the country is virtually unrecognisable to the Third World country he fell in love with nearly 70 years ago.

He said, today, Israel is considered the world leader in anti-terrorism operations, and every Western country seeks advice and counsel from Israeli security and intelligence services to counter threats by ISIS, homegrown radicals and other terrorist groups.

He praises Israeli security apparatuses for honing their skills, and says some of the attacks that have occurred in Europe "could not" happen in Israel.

"The groups committing the attacks would have been infiltrated and discovered here by our security services before they were able to attack," Arens said. "Lone wolf attacks are, obviously, more difficult."

Arens is also known as one of the 19 MKs who voted against the Camp David Accords and the peace treaty with Egypt. Today, he admits that the treaty was a key factor in the fact that Israel and Egypt have not gone to war since 1973.

"Of course I was not opposed to making peace," he said. "And I wasn't necessarily opposed to making some territorial concessions to close the deal. But I think the Yom Kippur War was the greatest victory in the annals of warfare.

"That was our last conventional war very much because of that victory: Egypt and others realised they had no chance against the IDF after starting a war with that sort of surprise, and ending up with us 101 kilometres from Cairo, the Egyptian 3rd army surrounded, Damascus within artillery range and them begging for a ceasefire.

"So we came to the negotiations with very strong cards, and I didn't think we had to beg them for a deal. It was a terrible sign to send to any aggressor that any territory they lose while attacking us will be given back. It was unprecedented."

Despite the passage of years, one point from that period of time remains sore - the fact that PM Begin asked Labourites Moshe Dayan and Ezer Weizman to accompany him to Camp David, which Arens believes prevented Begin from holding out for a better deal.

Arens said: "I know that both [Dayan and Weizman] put a lot of pressure on him to give in. It is very puzzling that he didn't ask me to come with him?

"I was the chairman of the Knesset Foreign Affairs and Defence Committee at the time. He also didn't ask any of his old Etzel comrades like Yaakov Meridor or Chaim Landau to accompany him."

If there is any area in which Arens feels Israel has failed to live up to the promise of its ideals, it is vis-à-vis Arab citizens of Israel.

He says it took the first intifada, followed by the 1991 Madrid Conference, to get ordinary Israelis to understand that the country must address the aspirations and desires of the Palestinian people living both as Israeli citizens and in Judea and Samaria.

"You can't say 'they' have a problem. We have a problem," Arens said. "They are our citizens and if we don't manage to integrate them into our society, into making them good citizens of the State of Israel, into having them be satisfied to be citizens of the State of Israel - then we've got a problem.

"If 20 years from now, a fifth of Israel's citizens feel alienated, hostile to Israel, prepared to participate in terror attacks in Israel, we're going to have an enormous problem. So it is imperative to address this point."

He says two Arab MKs - Zouheir Bahloul (Zionist Union) and Esawi Frej (Meretz) - are "excellent" Knesset members.

In contrast to many Israelis who feel the Palestinian issue in Judea and Samaria is a "ticking bomb" that will explode in Israel's face, Arens says confidently that time is working in Israel's favour.

"So, in that sense, I don't see what the rush is to give things away," he said.

"As I said before, not only are we strong militarily, but we're also strong economically. We have ongoing aliya, including from wealthy, Western countries. And, after all, we are talking about pieces of Israel, not some far away colonial empire.

"I've already spoken about what the immediate consequences of that unilateral move would be - a Palestinian terror state."

He added: "Listen, Israel is certainly the biggest success story of the 20th century for sure, perhaps of all time."