Finance Minister Arun Jaitley on Wednesday launched a no-holds-barred attack on Congress President Rahul Gandhi and his family and said he understood only the arithmetic of money and not issues related to national security. Intervening in a debate on the controversial Rafale fighter jet deal in the Lok Sabha, he said it was a tragedy that the nation's "grand old party is today headed by a gentleman who doesn't even understand what a combat aircraft is". Jaitley said the Congress and Gandhi were resorting to the simple argument of "Rs 500 (crore) versus Rs 1,600 (crore)" -- an apparent reference to the difference in the price of aircraft in contracts signed by the UPA government and the current government. "There is a reason for that. Some people and families in India only understand the arithmetic of money... They don't understand national security but only 'paisa'," he said. Without naming the Gandhi family, he asked why was it that one family's name came up in the Bofor's case, the National Herald case and the AugustaWestland case. "Had it been one case, I would have given them the benefit of doubt. But three is a bit too much." Referring to a dialogue in the famous James Bond movies, the Finance Minister said: "If it happens once, it's happenstance; if it happens twice, it's a coincidence; but if it happens thrice, then it's a conspiracy. "And today conspirators who have played with India's national security have the audacity to raise questions on a defence deal." Dismissing Rahul Gandhi's allegations of irregularities in the Rafale deal, Jaitley said he "took unprecedented liberties with truth" while making those charges. "Some people have a natural dislike for truth. From first to last -- every word spoken (by Gandhi) in the last few months has been utterly false. "It is a big tragedy for the country's most grand old party which was once led by remarkable leaders that it is today being led by a gentleman who doesn't even have the basic understanding of what a combat aircraft is."