As it turned out, Iran has more than one uranium enrichment facility. This pushed concerns to a head.

"Iran is breaking the rules that all nations must follow," US President Barack Obama stated.

It sent signals to world leaders that the time to act is now. Russia, which usually calls for diplomatic influence rather than further sanctions on Iran, wants full disclosure, or else repercussions will follow.

“We must create comfortable conditions to facilitate Iran's co-operation, and must create incentives,” President Medvedev said at a Pittsburgh press briefing.

“Several stimuli could be adopted, which I have discussed together with the US president. If those incentives don’t work and there is no co-operation, then other mechanisms come into force,” he added.

Dmitry Medvedev wants Iran to give UN nuclear inspectors all the information they want on the facility. Tehran says it’ll let inspectors look around, but the Iranian President’s tone still speaks volumes:

"Iran must do so and so, Iran must do this and that. We're saying 'what business of yours is it to tell us what we must or must not do?’” Ahmadinejad said during his speech in New York.

Iran will get its chance to prove its nuclear plans are peaceful at the upcoming six-party talks in New York. If it doesn't, Russia has given a wink to America that it could support the stricter measures which the US is calling for.

At the UN meeting, world leaders gave special focus to halting the spread of nuclear weapons. The Security Council unanimously agreed on disarmament, with Moscow underlining that it must go hand-in-hand with defense co-operation.

Russia and the US are leading by example, by cutting their own stockpiles. And both are poised to sign up to banning nuclear tests before the year is out.

"We will pursue a new agreement with Russia to substantially reduce our strategic warheads and launchers. We will move forward with ratification of the Test Ban Treaty, and work with others to bring the treaty into force so that nuclear testing is permanently prohibited," Barack Obama stated.

Such goals are now even closer following a sea change in Washington’s attitude on missile defense. It’s massively revising its Eastern European shield – a move that’s warmly welcomed by Russia, which is now withdrawing from plans to put weapons in its Baltic territory of Kaliningrad.

"Taking into consideration that the US plan has been cancelled, it's natural that I would decide not to place the Iskander missile system in that part of our country," Medvedev noted while speaking in Pittsburgh.

America’s new twist on politics chimes with Russia’s desire to see an end to a unilateral approach. And especially with Dmitry Medvedev’s call for a new global security architecture.

The Russian president promoted the initiative at a forum on international defense in central Russia at the beginning of the month. And it’s a goal that the major world players have been trying to make happen this week

It’s the kind of political outreach the world’s been waiting for, and a strong start to tackling issues that have blighted Russia-US relations for years.

But perhaps the key result in this week of major diplomacy is that, if Moscow and Washington can mend such deep scars, the world’s key players can focus on turning global threats into security and fear into trust.