Why was it urgent that Lincoln ensure the loyalty of Maryland at the onset of the civil war

1. Maryland had important weapons and forts
2. Maryland is north of Washington DC, without its loyalty the nations capital would be surrounded by the confederacy
3. Maryland was the center of US industry and manufacturing
4.all of the above

4. All the above

Explanation:

Territory of Maryland played very important role for the Union. The land of Maryland lies between Washington DC and Virginia. If Maryland was seeded from Territory, Civil war would be entirely different. As the order was passed to secede all the slaveholding land, Lincon does not allowed Maryland to secede from the territory and wanted to remain loyal. The population subsisting in west of Baltimore and north granted loyalities towards union. Moreover, it was important to keep control of the border state for the victory of Union, it also facilitates the union by advantage of money, factories and army.

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