As we now know, the US chose the second course of action and took a series of aggressive postures all over the world that led to animosity, fear, and war. That period of world history is known as the Cold War, an era in which the major military powers stared each other down while trying to seize territory and influence from each other. The Cold War was characterized by intense regional warfare in Korea, Vietnam, Israel, and Afghanistan.
Meanwhile, and at the same time, the rest of the world was taking the first course, building the United Nations, developing international treaties to avoid war and, especially, to avoid committing crimes against humanity. The US was in the forefront of this movement in the aftermath of WWII, when Eleanor Roosevelt lent her considerable influence to the UN and the Geneva Accords on human rights. But later presidents--Harry Truman and Dwight Eisenhower--decided to treat Russia and China as enemies and developed a policy of "containment".
This policy of containment and use of force to deter enemies is exactly what Marco Rubio prescribes as a foreign policy--not surprisingly, since his advisors were also advisors to George W. Bush. So Rubio tells us that
physical strength and an active foreign policy to back it up are a means of preserving peace, not promoting conflict.Rubio thus makes clear that he did not learn anything from the disastrous wars of G. W. Bush. If physical strength and an active foreign policy are a means of preserving peace, why did Bush's presidency take over a generally peaceful world from his predecessor and turn it into two major wars that continued during his entire administration? The answer is, of course, that Marco Rubio and the neoconservatives who advise him are completely wrong, that his policy will lead to war, not peace, and trying to intimidate nations is a good way to consolidate the power of despots who rule them.
Worse than simply advocating a foreign policy of belligerence against one country, Rubio proposes to attack (either physically or diplomatically) three powerful nations at the same time: Iran, Russia, and China. This policy, if carried out, would undoubtedly complete the destruction of the American economy begun so calamitously under G. W. Bush.
Rubio seems in love with the idea of a powerful US dominating the world's nations and dictating the terms of peace. The world has become too large for that, however. The techniques of asymmetric warfare are too well-known. The rebels in Afghanistan successfully fended off the Russian army. The Communist forces in Vietnam threw off the yoke of colonial oppression and sent the better-equipped and better-trained American forces back home.
Rubio and his neo-con advisors criticize Obama for being too risk-averse. They do not explain, however, how the US could prevent Russia from prevailing in the Ukraine, or prevent China from dominating the South China Sea. Rubio seems to believe the simple posting of military force in opposition would convince the Russians to abandon Ukraine or the Chinese to give up their designs on Hong Kong and Taiwan.
The problem that Rubio faces is not that his plan would fail, but that it would lead inevitably to hostilities between the US and countries whose assistance we will need to meet the challenges of global climate change and growing shortages of water and agricultural land. In an era when nature has provided mankind with a challenge we may not survive, we need to abandon our territorial ambitions and lust for wealth in the name of a greater good, the survival of the planet. Rubio and his pals ignore this fact. Their election to power would bring disaster, not just to the US, but to the whole world and all its inhabitants.