That is the biased narrative that we have been told for centuries, and it doesn't match recent research. Diseases happened first, they travel faster. The population affected devolves into chaos as disease often kills 9 in 10 and leave them without ruling and without those with specialised knowledge. Basically society is broken, the traumatised survivors are the ones that face the Europeans.

> military, political, administrative, trades

The civilisations of the Americas were trading with each other. Many of them had highly structured political and administrative centers. Just research the Inka for example, they had an administrative structure that in many ways is better than their European counterparts, a good example is how they eliminated hunger in the Empire. They had mechanisms in place to prevent the population dying of starvation, they were able to feed their whole Empire, that is not easy and requires a ton of accounting and planning.

Do not dismiss the civilisations of the Americas, and think that there is a ladder of evolution in which Europe is somehow higher. These civilisations were very advanced, and had they been able to survive in their own path, who knows where we'd be.

As for military, just check how fast the Spanish conquistadors changed from their equipment and garments to the native ones because they were better suited for work in the tropical climate, and how bitter were the confrontations with the pockets of resistance.

Disease is the key factor. Recent figures such as 90% dying from diseases is a devastating blow to any civilisation, there is no recovering from that.