We have grown accustomed to the deterrence theory formulated as the Cold War began. The concept covers “nuclear deterrence” down to the last detail. Nuclear deterrence—or, more accurately, the “balance of terror” and mutually assured destruction theory—constituted a key element of the Cold War and gave rise to several important results.

The first was how this idea facilitated the independence of the majority of African, Asian and Latin American states by means of revolutions supported by the Soviet Union and the Eastern Bloc against the old colonial powers. Second was the US inheriting the legacies of the old colonial powers, particularly those of Great Britain and France, in the 1950s. A third was the entrenchment of bipolarity, between the US and the Soviet Union, as proxy wars and military coups spread across the world.

The logic of deterrence appealed to the mindset of American, Soviet and European leaders who resorted to military intervention whenever they felt that their direct interests were under threat. The other side was aware that it had to balance its interests in choosing where to fight and where to accept defeat. That logic was also based on an implicit understanding that each superpower had its own private “backyard”—its sphere of influence—where it was not to be approached or manipulated. Instead, competition and confrontation were tolerated in other, less exclusive, arenas.

Since the 1950s, we have witnessed several interventions of all kinds, sizes and aspects: in Korea, Iran, Hungary, the former Czechoslovakia, Cuba, Indochina, the Middle East, and several Latin American and African countries.

Wars, coups, troop depoloyments, and military incursions aimed at toppling leaders of all political stripes were the defining feature of that long period of competition between these two axes. Even in the electoral campaigns of European democratic parties, the issue of nuclear armament formed a significant part of the manifestos of Right-wing, Left-wing and liberal-leaning parties—underlining the most dangerous theater of confrontation during the Cold War.

To highlight how important this issue was, we can take an example from British Labour Party MP Gerald Kaufman. He famously described his party’s 1983 election manifesto as “the longest suicide note in history”, because at that time his party, under the leadership of the leftist/pacifist Michael Foot, insisted that Britain unilaterally abandon its nuclear weapons. That “suicidal” manifesto deprived Labour of power until 1997.

Thus deterrence as a concept is highly significant to relations between countries. It is also realistic and reasonable, whatever your moral beliefs about the issue. The world of politics is based on interests, but there must also be a sense of prudence based on the prevailing circumstances. In other words, sometimes compromise is required, while at other times one must remain steadfast, depending on the situation. Perhaps, among the most significant characteristics of the successful leader is knowing when to appease and when to threaten, with whom to act tough and with whom to be lenient.

Throughout the long US–Soviet conflict, the world witnessed a series of mutual challenges between the two superpowers: The Soviets imposed their will by crushing the Hungarian uprising in 1956, in the face of Washington’s incompetence. Then, in 1962, President Kennedy confronted Soviet leader Nikita Khrushchev by setting up a naval blockade of Cuba during the now-infamous Cuban Missile Crisis, when the USSR attempted to install intermediate-range nuclear missiles in Cuba as a response to Washington’s deployment of nuclear missiles in Turkey. Ultimately, Khrushchev had to swallow his pride to avert disaster. But, Moscow soon took back its place of power, cracking down on the “Prague Spring” in the former Czechoslovakia in 1968.

The confrontation between the two superpowers continued throughout 1979 as conflicts ensued in Iran and Afghanistan and the Middle East became embroiled in the Arab–Israeli conflict. Despite his success in sponsoring the Camp David Accords, President Carter’s response to the Iran hostage crisis was weak, leading to his crushing electoral defeat by Reagan’s Republican Party hawks in November 1980. During the tough Reagan presidency, Soviet leader Mikhail Gorbachev faced the US’s strategic extortion with excessive moderation and conciliatory compromises, provoking the ire of his domestic rivals and precipitating the collapse of the Soviet Union.

Today, President Obama claims to have been elected into office twice on the basis of his anti-war election campaign. Thus he is content with making threats and denunciations and imposing economic sanctions in the continued strategic confrontation with a reinvigorated Russia led by ambitious no-nonsense leaders.

Obama and his team seem like starting their bids with Moscow as well as Tehran by announcing in advance that Washington has no intentions of going to war. Such an announcement—as we can clearly see—not only reassures Washington’s enemies, but gives them a freehand to do what they want.

Obama followed this feeble policy in Syria while Iran and Russia publicly and directly supported President Bashar Al-Assad with personnel and weapons. The White House’s barrage of empty threats and red lines were unceremoniously dismissed. Such US passivity has not gone unnoticed by Vladimir Putin; indeed, they have revived Moscow’s hopes of reclaiming its traditional spheres of influence, particularly in the former republics of the Soviet Union. The annexation of Crimea is just the start.

Where will Putin’s ambitions, fed by Moscow’s bitterness at its defeat in the Cold War, end?

A lot depends on how President Obama reacts. Thus far, Washington has concentrated on threatening economic sanctions, international isolation and a number of other measures it has convinced itself will pressure the Russians into losing their growing confidence in their capabilities. Earlier this week, some in Washington thought of reminding Russia that the “balance of power” between the two states is titled in favor of the US.

Well, perhaps there is some truth in that. Having somehow overcome its crushing economic crisis thanks to Obama’s astute domestic policy, the US is now in a better position to confront external threats. However, much depends on the current US administration’s belief in what constitutes an effective and realistic foreign policy against rivals who are ready to play the brinkmanship game.

The reality of the situation now is that the threats from Moscow and Tehran are creating new realities on the ground.