Pletcher's Diplomacy of Annexation: Texas, Oregon & the Mexican War

Introduction

American history, while relatively short in terms of all recorded history, occupies millions upon millions of printed pages, online sources, and scholarly works. Among those works, David M. Pletcher's The Diplomacy of Annexation: Texas, Oregon and the Mexican War, published in 1973, is considered by many to be one of the most pivotal studies on this period, and it continues — decades after its writing — to be discussed and cited by scholars and experts alike. This paper presents the major theses Pletcher advances in his book, along with the evidence and arguments he uses to support them, in order to reach a fuller understanding of both his work and its subject matter.

Territorial Expansion and the Annexation of Texas

To clear up some common misconceptions about Texas, Pletcher dismisses the false — and somewhat candy-coated — notion that Texas was gained by the United States as the result of diplomacy with Mexico. He makes an important clarifying point: while many mistakenly credit President Polk with the annexation of Texas, the Texas issue was in fact already resolved by the time Polk took office. It had been completed by his predecessor, President Tyler, just days before Polk assumed the presidency.

By the 1830s, Texas had become a kind of dictatorship on the border with the United States. By 1836, Sam Houston had been "elected" President of the Republic of Texas, and American troops had to be sent into the region to literally fight for its custody. From Pletcher's viewpoint, this episode reflects a common theme running throughout his work: the assertion that the United States' acquisition of territory was far more than a matter of land ownership. It was, in his telling, a mission to protect a new nation and a new way of life.

The Takeover of Oregon

When discussing the acquisition of Oregon, Pletcher puts forward an interesting thesis that is reinforced by historical evidence. He acknowledges that, in some respects, the push for Oregon was driven by a growing United States' desire for more territory — particularly territory rich in natural resources. However, he argues that considerably more was at stake than simply acquiring additional land for settlement.

The Treaty of 1818, proposed by the United States to Great Britain, had offered the U.S. sole occupation and control of Oregon, but Britain contested this claim. As a result, Oregon remained a jointly occupied territory of both nations until 1846. Drawing on this history, Pletcher makes the compelling argument that ownership of Oregon was necessary not only for national expansion, but also to fulfill the promise of the Revolutionary War itself — complete independence from the British Crown. What appears on the surface to be a straightforward territorial dispute is thus revealed, in Pletcher's analysis, to be a far more complex issue tied to the very foundations of American national identity.

Conclusion

History has always been a subject open to interpretation and debate. In The Diplomacy of Annexation: Texas, Oregon and the Mexican War, David M. Pletcher not only explains a complicated historical topic in rigorous detail, but also draws meaningful parallels between the past and the present. Decades after its publication, the work continues to stand on its own considerable merits, remaining an essential reference for anyone seeking to understand the forces — political, economic, racial, and ideological — that shaped the territorial formation of the United States.